I wanted to highlight this Channel 9 interview with Richard Murillo who is a lead developer at Microsoft responsible for building and maintaining the internal applications used by our legal teams.
In this video Richard does a great job of demonstrating how his team makes heavy use of Visual Studio Team System to collaborate on projects and implement software development processes. Richard's team actually uses each of the process templates included with Team System: MSF for Agile Software Development and MSF for CMMI Process Improvement. In this manner they can adapt their processes to the requirements of each project they undertake.
Richard makes a pretty compelling argument for using Visual Studio Team System. If I didn't know better I'd say he's gunning for my job... <g>