There's a growing revolt among Microsoft TechNet & MSDN subscribers who are frustrated that they can't yet get Vista SP1 and test their software on it. This can't be good news for anyone hoping that SP1 will have better compatibility. While SP1 has been released to manufacturing, and pirate copies are easy to find, Microsoft is withholding it from subscribers until early March. According to the article, some frustrated users are upset enough that they plan to abandon TechNet entirely and turn to piracy.According to the Technet blog, they have pushed up the date to before the end of February, though no exact date is mentioned.

http://www.computerworld.com/action/article.do?command=printArticleBasic&articleId=9061838
http://www.google.com/search?q=vista+sp1+tpb
http://blogs.technet.com/technetplussubscriptions/archive/2008/02/11/technet-plus-sp1-availability-update.aspx