The iTunes update adds iOS 6 compatibility, among other features.
Intel Mac users will like Snow Leopard's smartly designed interface enhancements, and its Exchange support is a must-have (especially with Outlook for Mac on the way). With a ton of technological improvements, Snow Leopard is worth the $29 upgrade fee.
Apple has posted a revised updater for the OS X 10.6.3 update, which should appear in Software Update on systems for which it applies.
Users have reported an issue with their Mac when entering sleep mode. After installing the Mac OS X 10.6.3 update and attempting to put their Mac to sleep, the system freezes.
An ongoing issue that people have had with the latest 10.6.3 update is with changes to the Finder's handling of files when copying to mounted SMB shares.
When applications crash or are forced to quit during a hang in OS X, the system will bring up a crash reporter window that contains diagnostic information about your system, which applications were open, and memory traces for the threads that were open.
The forthcoming update to Mac OS X Snow Leopard, 10.6.3, will incorporate over 90 components including several bug fixes and solutions for crashes.
An ongoing issue with OS X 10.6.3 seems to corrupt graphics on external displays when you present in full screen with "mirrored" displays. The display will work and show the mirrored desktop in the Finder, but when applications take over use the display to show full-screen presentations, media, or other purposes, the graphics will garble and can only be fixed with a restart.
Apple has updated a couple of knowledgebase articles, one of which covers how to tackle problems with Mail connectivity in OS 10.6, and others that discuss the enabling of Magic Mice gestures and how to prevent a specific iMovie crash in OS 10.6.3.
Apple has released a new version of GarageBand for OS X, which specifically adds support for importing projects made on GarageBand for iOS devices.