First off thank you to everyone you commented, emailed, and otherwise gave direct feedback to Mike Nash when he announced the Windows Vista SP1 had RTM'ed . It became very clear form all the feedback from folks like yourself that you wanted the bits, sooner rather than later. I do not know if you realize we take your satisfaction and dissatisfaction very seriously. You may not know this, but as the TechNet team we work hard to make sure you are heard.
Well you guys gave the feedback and the availability dates are being moved up, now while I cannot give you exact dates I can tell you this:
I will put a brief announcement when it does go live. So what were the problems, well the issues seemed to stem from various Vista drivers, Mike talks briefly about that here: Windows Vista SP1 availability for technical customers
To learn more about what is in SP1 take a look here:
TechNet TechCenter: Windows Vista Service Pack 1 (SP1)