Apparently the up coming dashboard update that enables the new disc format is not compatible with some older Xboxes, probably related to the type of DVD drive it has inside.
The good news if it is true is Microsoft will replace all affected Xbox consoles with a new 250GB Slim for FREE.
http://www.digitalspy.co.uk/gaming/n...l-systems.html
http://www.neowin.net/news/microsoft...ew-game-format