Windows Vista Service Pack 1 (SP1) is being released to manufacturing on Monday 4 Feb and will start being available to customers in March, starting with Microsoft Volume Licensing customers.
Windows Server 2008 is also being released to manufacturing on the same date and will be available to new customers on March 1. Microsoft Volume Licensing customers with active Microsoft Software Assurance coverage or an Enterprise Agreement will be able to download the new Server software toward the end of February as part of the joint Microsoft SQL Server 2008 and Visual Studio 2008 Heroes Happen Here launch event
Contrary to reports SP1 will not be RTW (release to web) today.