Contrary to rumors going around the web regarding an alleged screencap of an internal Sharepoint site listing the Vista SP1 release date, it's going to be a while before the masses see SP1. Biplab Paul a Technical Consultant at Microsoft has made a post on his blog detailing the roll out of SP1.
When will SP1 be shipped?
- Mile Stone 1 (Feb 4, 2008): Available to OEM and Retail Channel
- Mile Stone 2 (Early March 2008): Vista SP1 Volume Licensing Availability
- Mile Stone 3 (Mid March 2008): Vista SP1 availability through Windows Update/MSDN/TechNet
- Mile Stone 4 (April 2008): Will be pushed via Automatic Update
News source: Biplab Paul's Technet Blog