I saw this article while searching for the use of animated logos as "please wait" icons.
http://msdn2.microsoft.com/en-us/library/aa511284.aspx
It is part of a larger UX guidelines kit from MS regarding VIsta.
http://msdn2.microsoft.com/en-us/library/aa511258.aspx
Amazingly, it is quite objective and even harsh against certain Microsoft tendencies. I think it’s awesome that a company can be that objective and publish "bad things" about their previous design choices. I am going to read it in more detail. Great job to the authors.
With that said, I am very disappointed in the UX of Vista. It is slower and harder to use. UAC is the worst decision in the world and will lose them lots of good will.