Never had this happen ... after ALL of the f*cked up user names, I was booted in the middle of a match, given an Xbox Live error screen, followed by a prompt to change my user name under a "terms & services" violation.
All of this for "TreyvonIsGuilty". I've seen people with "n*gger" in their name and a play history of 100's of games. "TreyvonIsGuilty" triggered an immediate in-game change.
New name: "TreyvonGonzalez" ... there's NO way that's in violation of any terms & service statement.