Ok, I must have been away from this world for some time. Apparently Microsoft's new game console will be called Xbox 360. You can read all about it here.
A few years ago, when Microsoft released its first Xbox, there was some student analyzing traffic that was crossing the encrypted bus (between CPU and peripherals I think), for its thesis. As a result, different small companies released mod chips that were able to hack this bus. After mod'ing your Xbox, you were able to run copied games (not that I approve that). You could even run Linux on your Xbox. After all, the first Xbox was a normal PC, with some proprietary stuff from Microsoft.
When the new Xbox will be released, the OpenSource community will be ready ... I can't wait ;)