A new book on Team Foundation server has just recently been released.  It’s an in-depth view of using the breadth of TFS 2010 capabilities and includes a lot of information on customizing and extending TFS.

I know the authors well (2 of them are on our team :)) and I can’t think of a better group of people to write the definitive work on TFS.  I recommend it for everyone responsible for managing a development process with TFS.

More here: http://www.edsquared.com/2011/03/05/Book+Professional+Team+Foundation+Server+2010+From+Wrox.aspx

Brian