Microsoft XNA Game Studio, the user-creation tool that allows you to make Xbox Live Arcade-quality games for the Xbox 360, has just been upgraded to 2.0. The most interesting improvements in the new version are the multiplayer networking APIs, which means you can actually create games like Jason Chen's Big Boob Robots that take advantage of Xbox Live's network support. Other than this, it's mostly improvements for developers that aren't that exciting for people who just want to play homebrew games. [MSDN]