Today, a build of SP1 was posted to Windows Update and it was inadvertently made available to a broad group. The build was intended only for our more technically advanced testers, and was meant to only be offered to those with a specific registry key set on their PC. For general availability, we are still planning to make SP1 broadly available in the mid-March timeframe.
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Man, the Vista SP1 release has turned into one giant Charlie Foxtrot.