Snow Leopard. Even the name seems to underpromise -- it's the first "big cat" OS X codename to reference the previous version of the OS, and the list of big-ticket new features is seemingly pretty short for a version-number jump. Maybe that's why Apple's priced the 10.6 upgrade disc at just $29 -- appearances and expectations matter, and there's simply not enough glitz on this kitty to warrant the usual $129.

But underneath the customary OS X fit and finish there's a lot of new plumbing at work here. The entire OS is now 64-bit, meaning apps can address massive amounts of RAM and other tasks go much faster. The Finder has been entirely re-written in Cocoa, which Mac fans have been clamoring for since 10.0. There's a new version of QuickTime, which affects media playback on almost every level of the system. And on top of all that, there's now Exchange support in Mail, iCal, and Address Book, making OS X finally play nice with corporate networks out of the box.

So you won't notice much new when you first restart into 10.6 -- apart from some minor visual tweaks here and there there's just not that much that stands out. But in a way that means the pressure's on even more: Apple took the unusual and somewhat daring step of slowing feature creep in a major OS to focus on speed, reliability, and stability, and if Snow Leopard doesn't deliver on those fronts, it's not worth $30... it's not worth anything. So did Apple pull it off? Read on to find out!

Installation

Interestingly enough, installation is one of the few parts of Snow Leopard that's dramatically different than previous versions of OS X. Unlike Microsoft's subtle nudges towards clean reinstallation of Windows 7, Apple's quite proud of the new 10.6 installer, which upgrades in place, quarantines incompatible apps and plugins in an "Incompatible Software" folder, and boots you right back up with little to no user effort. Seriously, you just stick in the disc, open the installer, enter your password and go -- that's it. You don't even have to reboot off the DVD. Of course, that made us a little uneasy, since we've always chosen Archive and Install to get a fresh OS, but you can't have cold feet here -- that option's been removed. We've been told it's now the default action behind the scenes, but the bottom line is that you have to trust the installer more than ever before -- and while we didn't have any major problems, it would be nice if we could force a new install of the OS without having to wipe a disk.

Installation itself took about 45 minutes on most of the machines we tried, although we did run into some snags once things were complete. We didn't have any problems with the more pristine MacBook Pros in our fleet, but one of our production machines is a cranky older iMac that's been in constant use for over two years without a system rebuild, and when it restarted the desktop pictures were all set to the defaults, the System Preferences app wouldn't launch from the Apple Menu, our MobileMe sync states were a little confused and Spotlight began reindexing all the external drives. Fixing these problems didn't take much, but if your machine is already acting up don't expect everything to go perfectly.

Other installation notes: We were promised 6GB of storage savings with 10.6, and Apple more than delivered -- we got anywhere from 10GB to a whopping 20GB back after installation. Rosetta is no longer installed by default, so if you're still rocking some legacy non-Universal apps you'll want to make sure and install it. Printer driver installation is much smarter, installing drivers only for those printers you've used in the past and printers that appear on your local network. We have no idea why Apple continues to insist on installing language translations by default, but they're much smaller now at 250MB.

Overall, installing Snow Leopard is just like installing any other major OS update: it works great, except when it doesn't. The process itself is fine (in fact, Apple has even built in some safeguards to let you pick up an install if your computer dies or is shut off half way through), but it's the little kinks you have to work out afterwards that can be tricky. If you haven't loaded up your system with hacks and tweaks chances are you'll be fine -- and if you're living on the edge, well, you're probably used to doing some extra work around upgrade time.

UI enhancements

Dock Expose

Previous OS X releases have brought major UI features like Expose and Dashboard with them, but there's nothing that major in Snow Leopard, although the various tweaks to the system are certainly appreciated. The biggest new feature is Dock Expose, which, as you'd expect, simply links Expose to the Dock. Holding down on an app's icon triggers Expose for that application's windows, and if you drag a file onto an app, you can then select which window you want to drop it into. It's definitely nice, but it's not earth-shattering. Here's a little video of it in action:

And... that's really it, as far as UI changes go. There's some other minor stuff, like better PDF text selection in Preview, new glass-look menus for the Dock, and alphabetical / per-app window organization choices in regular Expose when you press command-1 or command-2, but overall it's all extremely iterative and incremental -- welcome, to be sure, but not major. The new Finder, on the other hand, is both major and more than welcome.

Notable app changes

Finder

It's hard to explain how dramatically improved the Finder is now, because there's nothing externally different beyond those file previews and an icon-size slider in icon view. Suffice to say that the Cocoa rewrite has simply made things better: opening folders with thousands of items is instantaneous and scrolling is just as fast; network connections are snappier; and everything hums about with essentially zero lag. Sure, all the old Finder quibbles like inconsistent windows states and those damned .DS_Store files are still there, but trust us -- speed cures all ills. At least until we dump another couple thousand files into the system and slow things down again.

QuickTime X

Like the Finder -- and, really, all things with Snow Leopard -- QuickTime X is a set of major changes wrapped in seemingly-minor interface tweaks. Although the big change for users is the "dark" interface with a title bar and controller strip that disappear during playback, underneath QuickTime has been entirely rewritten with hooks into modern OS X components like Core Video, Core Animation, and Core Audio. That doesn't mean much if you're just playing back an MP3 or a single video, but remember that QuickTime is more than an app -- it's the entire media layer for OS X, so the Snow Leopard rebuild will have big consequences down the line.

That said, there are some notable changes with QuickTime Player: there's a new screen recording tool (we made all the videos in this post with it), you can record right off your built-in iSight, and there's a new iPhone 3GS-like "Trim" tool to cut your videos fast.

That glossy title might come at a steep price for some of us -- at least at first glance. QuickTime Player X has certainly added some welcome new options for most, but for QuickTime 7 Pro users, things get a little confusing. If you've already got Pro on your system and do a straight install, you'll end up with the standard new QuickTime -- which means a lot of what you're used to will be missing. Hell, there isn't even a preferences dialog -- so say goodbye to presenting movies on a different monitor, or choosing a default full screen setting. The changes also means that you can't do quick'n'dirty edits by copy-and-pasting anymore (a favorite of Engadget editors), and export options have been reduced to presets for iPhone, iPod, Apple TV, MobileMe, and YouTube.

On top of that, some QuickTime-dependent apps seem like they need a rewrite to work correctly -- we couldn't get our Turbo.264 HD stick to function, and other QuickTime programs we tried seemed similarly stressed. Oh, and those screen recordings? They're encoded with some combination of H.264 and AAC audio that didn't play nice with Viddler out of the box -- and YouTube's uploader refused to load under Snow Leopard (we had a number of server errors), so we ended up uploading all these screencasts from a Windows machine. That may not be the case for all, but it was for us.

This won't be too much of an issue for users who are sticking with the basic QuickTime functionality, but for those of us who've become accustomed to Pro, it may be a little shock. Interestingly, Apple let us know that you can actually re-install QuickTime 7 Pro from the Snow Leopard disc (and from your Utilities folder, oddly), but if you hop right into a standard upgrade, it's amazingly easy to miss (we did on multiple systems).

Safari 4

If you're thinking of upgrading to Snow Leopard on day one, chances are you're already running Safari 4, since it's been available since June. The big changes in 10.6 are (obviously) 64-bit support, which here translates into much faster Javascript performance, and a new browser plugin architecture that runs individual plugins as separate instances. That means if a plugin like Flash crashes it won't take the whole app down with it, but sadly, we weren't able to test it -- for maybe the first time ever, we couldn't crash a browser. Hopefully our good luck rubs off on you.

Exchange

By any measure, the most important new networking feature of Snow Leopard is built-in support for Microsoft Exchange in Mail, Address Book, and iCal. Since we're not heavy Exchange users, we won't go in-depth here -- our man Michael Gartenberg has got you covered there -- but in our quick tests we found setup to be simple and the integration to be flawless. It's hard not to look at how well Snow Leopard integrates with Exchange and see exactly why Microsoft decided to kill Entourage and bring a proper version of Outlook to the Mac, but that's not happening for a long while -- until then, we think OS X users who need Exchange will be pretty happy.

Compatibility

Here's where it gets a little rough. Although Snow Leopard is ostensibly just a polish and repair job on Leopard, there've been enough changes under the hood so that plenty of things are likely to break -- or at least not play nice. As with the installation, if you're running a stock or close-to-stock system, you probably won't run into any problems, but if you've got a setup as tweaked as most of those in the Engadget labs, you're going to run into some issues.

The biggest compatibility-breaker is the demise of InputManager plugins in 64-bit apps, which means things like Unsanity's Application Enhancer framework and Safari plugins like 1Password and Glims are now broken (or at least not really playing nice). InputManager plugins have had a long and sordid history, with many claiming that they're unstable hacks built on what's essentially a security hole, but now that they're gone the only thing to worry about is how to replace all the utilities and applications that depend on them -- 1Password's developers are already beta-testing a 10.6-compatible update, but we have no idea how something like Chax will soldier on. If you've got a critical workflow that depends on an InputManager plugin -- and although that's always been a bad idea, we're sure some of you do -- then we'd advise holding off on the 10.6 upgrade until you work something out, since we saw some random freak-outs (like the one pictured) when we forced Safari into 32-bit mode to run 1Password.

We also noticed problems with old standbys like Growl, GrabUp and Skitch -- really clutch go-to applications that seemed to buckle under the 64-bit noise. Although we could start them in 32-bit mode, nothing seemed to work exactly right, and we're pretty sure we spotted Growl making off with a ton of free memory when we weren't looking. We also had trouble getting our Sprint Novatel U727 3G stick working, although our Verizon card was fine. Again, we're sure all of this is going to be updated, but if you're like us, the bugginess will prove maddening at times -- enough to make us consider waiting out the upgrade on some of our other machines.

There were some other head scratchers we saw on various systems, too. On a 17-inch unibody we were putting through the paces, the WiFi inexplicably has gone out and we have yet to get it working again. On a 15-inch, older generation MacBook Pro (3,1), Spotlight will only fetch search results in the dropdown -- results in a Finder window come up empty. More annoyingly, on two other, newer models we were testing with, Safari crashes out when booting into 32-bit mode -- meaning even Apple's workaround doesn't seem to... er, work.

That's the bad news, though. The good news is that almost all of our regular, non-plugin, non-third-party-framework, non-hack apps worked just fine. Office, Photoshop CS3 and CS4, Tweetie, Firefox 3.5, Ableton, Fluid -- you name it, it ran without a problem. Like we said, if you're running things close to stock you're going to be fine, but we tend to kit out our rigs with a ton of little hacks to really speed up our workflow, and that's the stuff that's broken in Snow Leopard. It's up to you to decide where on that line you fall before you commit to the upgrade.

Overall speed and stability

Compatibility with our various hackeriffic plugins aside, we found Snow Leopard to be just as stable and free from major hang-ups as Leopard. That cranky iMac we installed it on seemed to perk up a little, and while we don't think anything will ever make Firefox feel perfectly stable, we certainly didn't experience as many beachballs or other hangups while running 10.6. So yes, subjectively things seem fast and reliable, and the new Finder makes day-to-day usage seem positively zippy -- and the objective benchmarks tend to back that up.


As measured by XBench, Snow Leopard affects every Mac a little differently, but the basic outcome is the same: raw CPU performance goes up slightly, while the graphics numbers go down -- OpenGl performance in particular takes a big hit. We're not sure if this is due to our version of XBench not playing nicely with Snow Leopard or something else entirely, but we didn't notice any slowdowns while we actually worked -- or played a little casual CoD4. We're not deep into the benchmark scene, so we'd wait for some hardcore marks to hit before you race into fanboy battle with these numbers -- for now, just know that Snow Leopard certainly "feels" a little snappier than Leopard.

Wrap-up

Here's the thing about Snow Leopard, the single inescapable fact that hung over our heads as we ran our tests and took our screenshots and made our graphs: it's $30. $30! If you're a Leopard user you have virtually no reason to skip over 10.6, unless you've somehow built a mission-critical production workflow around an InputManager hack (in which case, well, have fun with 10.5 for the rest of your life). Sure, maybe wait a few weeks for things like Growl and MenuMeters to be updated, and if your livelihood depends on QuickTime you might want to hold off, but for everyone else the sheer amount of little tweaks and added functionality in 10.6 more than justifies skipping that last round of drinks at the bar -- hell, we're guessing Exchange support alone has made the sale for a lot of people. If you're still on Tiger, well, you'll have to decide whether or not you want to drop $130 on what's essentially a spit-shined Leopard, but if you do decide to spend the cash you'll find that the experience of using a Mac has changed dramatically for the better since you last upgraded.

Update: In the original version of the review we noted that QuickTime 7 Pro wasn't available for Snow Leopard. In fact, the software is available as a separate install on the disc itself and via the QuickTime 7 app in the Utilities folder.