Microsoft is going to let home brew developers make and deploy games for Xbox Live! How awesome is that?
Microsoft will provide the software for free, and you can use C# to write games that can target the Xbox 360 and the PC. If you want to share your game, it'll cost you $99, but eventually, developers will be able to sell their games through Xbox Live Arcade.
Links to the news:
This is a great move, and bound to generate hundreds of fun games that would never be made by a commercial game studio. Very cool, Microsoft!