Here's the list:
As to how it's determined, no one except certain staff know, for rather obvious reasons. Still, there has certainly been plenty of speculation and you can read all about it by joining this group:
http://www.chess.com/groups/home/cheating-forum
please tell me you folk haven't blacklisted people like a salem witch hunt because sore losers can't accept a loss. please tell me you have some other method to warrant sanctions. I am so miffed by this paranoia that i may just make it my calling to expose and bring attention to such absurdity. I can't think of anything more unbecoming and embarrassing as a modern day witch hunt due to soft egos.