A few months back, I did a Channel 9 interview on P2P and Collaboration in Vista.  It has been pretty popular on Channel 9 (~30k views), so I thought I would point other folks at it.  It is a pretty good 1 hour introduction to the overall P2P/Collab platform in Vista.  Let me know if you have questions or want to hear about other points in a follow up video.

http://channel9.msdn.com/Showpost.aspx?postid=165133