Using XBMC in order to get your Xbox to be a media center is fine in itself. It has not illegal repercusion.
Under the fair trade of use (or something like that), you are entitled to do what you want to your device, and Microsoft is entitled to block you from using their network if you do so (read the User Agreement).
Hacking and copying video games to play downloaded backups on the other hand is a whole different story, and this is what we do not encourage on the forum.
Last edited by Ycare; 03-21-2010 at 08:37 AM.