There was an update, and after the update the info about texture hacks went poof on steam. My theory is simple...
Seeing as how BO is heavy on the Cloud computing, this could cause a lot of lag if anything is accessed to much by to many people. They may have gathered hash values from the player skin .iwi or the .iwd as a whole and simply uploaded it to compair to a master hash value. If the value does not match ban is tripped. What I think happened is that the constant uploading of these files ended up lagging the cloud server and caused random lag to players. If you then remove this from the game and no longer upload the values the hack is no longer detectable.
Never the less the method to make this hack is simple, it uses the same methods and tools as MW2.
This version of CoD was a rush job and not recreated (hence using sound clips from WAW and some of the same models.) -_-