Mac OS X 10.6.2 Build 10C540 has just been seeded to developers and contains several fixes, even though it arrives just one week after the otherwise most recent build. To sum it up shortly, the new Snow Leopard build fixes a pretty serious data loss issue, which was first mentioned around the 13th of October. The bug was apparently related to guest accounts, and resulted in loss of huge amounts of data.
Also, the new build contains full native support for the all new Magic Mouse as well as an Airport issue with the new iMac and VMware, which just introduced a new version with improved 3D graphics called VMware Fusion 3. Finally, the new build also contains several minor fixes, such as an Apple TV graphics improvement.