
Gizmodo has an unconfirmed report that Microsoft banned a refurbished 360 from Xbox Live. While this isn't particularly unusual for a modded Xbox, this particular unit was Microsoft certified:
Seems like something else must be going on (like perhaps stupid user syndrome), unless the unit in question was somehow both refurbished and modded. Microsoft has yet to comment on the matter.
Microsoft Banning Xbox 360s for Life? [Gizmodo]