When a new OS upgrade costs US$29, you can be forgiven for thinking of it as a service pack. Such may appear to be the case with Mac OS X 10.6, aka Snow Leopard, which Apple has positioned as an under-the-hood upgrade whose new capabilities won't be so obvious to users, and thus not worth the usual $129.
I agree with that price assessment (if only Microsoft had made the same judgment about Windows 7), but I don't agree that what Snow Leopard offers resides merely under the hood. Instead, it provides many enhancements and some new features that Mac users of all persuasions will really like. (Note: The $29 upgrade price is for Leopard users; if you have an older Mac OS X version, US pricing is $169 to upgrade.) Much of Snow Leopard's focus has been internal. For example, Apple has revamped the kernel, included apps, and much of the OS itself to be 64-bit (to allow virtual addressable memory of 16 exabytes and physical addressable memory of more than 32GB). But until apps are rewritten for 64-bit and the new Mac models support that kind of memory, there's little immediate benefit — ditto for multicore enablement in the Grand Central Dispatch engine. But the revamped QuickTime X and Java engines should result in faster processing of streaming media and Java applets (such as on websites).
Putting aside these important but long-term changes, here are Snow Leopard's most immediately beneficial new features and enhancements.
1. ActiveSync and Exchange 2007 support
Following in the footsteps of the iPhone, Snow Leopard makes these Microsoft technologies native to the OS. That means Apple's email, calendar, and contacts apps work just peachy with Exchange 2007 server, giving users the same capabilities as Microsoft Entourage but with the better-designed, less-memory-intensive apps — Mail, iCal, and Address Book — included in OS X.
2. Exposé integration in the Dock
The Mac OS X Dock makes it easy to access applications, open documents, and common folders, a concept Windows 7 is stealing in its retooled taskbar. Open documents are even more easily accessed in Snow Leopard, thanks to the integration of Exposé. Now when you click and hold an app icon in the Dock, you get preview windows for each of its open documents, allowing you to switch easily among them or to close them, all without having to clutter your screen with document windows. I never cared much for Exposé in its traditional role (providing hot corners and shortcuts to open application windows), but I love the Dock-integrated Exposé functionality that Snow Leopard adds.
3. Automatic location detection
When you travel, it's easy to get mixed up as to when your appointments are, since your computer is still in your "home" time zone, and you have to mentally calculate the current time when looking at the calendar or clock. Sure, you can change the time zone in the Date and Time system preference, but it's easy to forget. So Snow Leopard changes the time zone for you automatically (if you set that as the default behaviour), using wi-fi mapping to figure out where you are — you will need to be connected to a wi-fi access point or router. iCal can also be set to adjust the times to the current time zone automatically, so your calendar always reflects the current times.
4. The new Preview is more like Adobe Reader
I have nothing against Adobe Reader, but I love that Preview now can open multiple PDF documents, display their contents as contact sheets, and show thumbnails of pages in a sidebar for easy navigation. In other words, it works a lot like Adobe Reader. That's one fewer app to launch — and since Preview loads much faster than Reader, I can get to my PDFs' contents much faster now.
5. Movie and screencast recording
Snow Leopard takes the formerly $35 QuickTime Pro and makes it a standard, free app in Mac OS X. That means you can record movies and — great for many marketing, education, and Web professionals — screencasts from your Mac with no additional software.
6. Systemwide automatic text replacement
Automatic text substitution as you type is nothing new; Microsoft Word has had it for more than a decade. But Snow Leopard lets you specify such substitutions via the Keyboard system preference, so you have a common set of substitutions available to all applications. Right now, only TextEdit, Mail, and various Apple apps use this common auto-text service, but if other software developers adopt it, you may finally get all your text-oriented apps to autocorrect the same way.
7. No more gesture segregation
I have a late-2006 model MacBook Pro at home, and it's frustrating that its gesture-capable trackpad supports only the first generation of touch gestures (one- and two-finger moves), not the second-generation three- and four-finger options. Snow Leopard fixes that, so gesture-capable trackpads now support all gestures, no matter what Mac model you have. (Of course, your Mac has to have a gesture-capable trackpad, so models before 2006 aren't helped out by this update.)