I just finnished reading Inside the Microsoft® Build Engine: Using MSBuild and Team Foundation Build and even though I know of several posting about this book I figure they could do with some more praise :)
I approached this book with and expectation that I already knew my fair share about the build process in Team System but was pleasantly suprised that there where a few nuggets that I was unaware of so it paid of to read it after all. Otherwise I must say that the book is well structured and is down to earth with a lot of practical examples from real world scenarios. I truely wish that I would have had access to this book back in 2005 when I started out with build automation in Team System.
The book is a must read for anyone considering working with build automation using Team System (atleast until VSTS 2010 comes out and changes it again). Also if you want to truely understand MSBuild and how your projects are built by Visual Studio (although you will come along way when working with Visual Studio without reading one single row of MSBuild script).
Personally I will keep my copy on my desk as a reference and flip through it when working with the nitty gritties of the build scripts.