Thanks to a confirmation on Computerworld, Gregg Keizer writes that the release of Windows Vista SP1 will be out on Tue. March 18.
Microsoft Corp. late Monday inadvertently confirmed that Windows Vista users will be able to upgrade to Service Pack 1 (SP1) starting tomorrow. (Tue. Mar 18)
"If Microsoft holds to plan, Vista users will see SP1 in Windows Update tomorrow as an optional download, but only if their PCs do not harbor one of the balky drivers. Alternately, users will be able to download a much larger stand-alone installer from Microsoft's download site, also beginning Tuesday."
So make sure Automatic Update is turned on so that you can receive it once it goes live to Automatic Updates or check out Windows Update.
Microsoft plans to roll out SP1 next month to users who have Windows Update set to automatically download and install fixes.
Thanks Satisfy Me