via Neowin (Confirmed by me)

Quote by neosmart

"Microsoft has just released an updated version of Windows Vista to technical beta testers. Build 5456 is available in either x86 or x64 flavors right now on Microsoft Connect. Neosmart just posted some additional information about this build:

"Some of the new features include a revamped Aero/DWM subsystem, and a completely overhauled and siginficantly less obtrusive UAP for all those that couldn’t stand the previous one. From what we have been told by Microsoft, the Time Zone bug that plagued previous builds of Windows Vista has been patched, and quite a few fixes in the Regional Settings and IME have been patched."