Huzzah! The talks from GameFest 2008 are up on MSDN.
Among this veritable cornucopia of goodies, you will find two talks from yours truly, Networking, Traffic Jams, and Schrödinger's Cat and Building Worlds with the Content Pipeline.
Eli spoke about Real World Content Pipeline Examples, while Mitch covered Creating Great Community Games and What’s New in XNA Game Studio 3.0, and Frank handled XNA Game Studio Performance: Multithreading and GPU.