I have just posted new VirtualPC activity documentation for TFS 2010 Community Build Extensions. This has been a really nasty set of documentation to write as getting this activity running raises a lot of issues over COM security; thanks to Rik and Andy (our SharePoint specialists at Black Marble who are therefore used to COM problems!) who helped get to the bottom the issues.
The best think I can say about this VirtualPC activity (and I wrote much of it) is don’t use it. Much better to use the Hyper-V one it is far more flexible, allowing control of remotely hosted VMS, or even better use TFS Lab Management