Apple has bumped Snow Leopard, the latest version of Mac OS X, to version 10.6.6. The hallmark feature of the latest OS update is of course support for the new Mac App Store (see “Peering Behind the Mac App Store Counter,” 6 January 2011). Upgrading to 10.6.6 places the Mac App Store’s icon in your Dock, adds a link to the store in the Apple menu, and prompts you to visit the store if you attempt to open a file that existing software on your Mac can’t read. Also included in the 10.6.6 update is a single security fix, addressing a potential vulnerability in PackageKit that could allow an attacker to run code on your Mac. Finally, the update addresses two bugs: a cropping issue with PostScript printing in landscape orientation, and an issue with erratic mouse pointer movement on Macs with ATI graphics cards when an external DVI display is connected.
With updates to Mac OS X, it’s usually easiest to let Software Update download just the code that applies to your specific Mac and version of Mac OS X. But you can download delta installers to update 10.6.5 to 10.6.6 (for both Snow Leopard and Snow Leopard Server, each about 143 MB) and much larger combo installers to update any version of 10.6 to 10.6.6 (again, for both Snow Leopard and Snow Leopard Server, each weighing in at a bit over 1 GB in size). As always, make sure you have a current backup before you update, and don’t interrupt the upgrade process once it has started.