As of 30 minutes ago, bans were handed out to all (or most?) of those who abused the Prestige Token Exploit. This info was released on the twitter page @fourzerotwo. Don't say we didn't tell you so.
This is a direct quote:
"Witness as the #MW3 ban hammer falleth. Prestige Token exploiters banned, stat reset & removed from leaderboards."
Please take a vow of silence for all those Gamertags that got banned for 2 days.

This interesting image was also released:

Posted: Jan 05, 2012 9:59 pm

Source: https://twitter.com/#!/fourzerotwo/status/155111552763166720/photo/1