It's not uncommon for Microsoft to unleash the Xbox Live banhammer once every few months. Rounds of banning are generally conducted for typical reasons -- piracy
and the like
-- but this ban session is a little different. We've received several tips on the matter, and Microsoft has issued a statement
on the Xbox.com forums saying that the console bans were the result of Xbox Live Marketplace "theft."
The company won't provide specifics on the kind of theft that took place, though there are some likely culprits. For example, there are known methods for downloading Xbox Live content for free (that we won't be sharing here) and presumably Microsoft has gotten wise. If you'd like to keep your account intact, then maybe, you know, don't steal.