Highest rated person

Anyone know what happened to "tigerpetrosian"? He was number one a couple of days ago but decided to resign all of his games.
http://www.chess.com/echess/profile/tigerpetrosian

I'm curious what tigerpetrosian's account closing means for siahkal, the current top-rated play, whose best win was against tigerpetrosian.
Edit: Although I now see that that win was from the recent mass-resigning of tigerpetrosian's games. So I apologize for my conspiracy-inspiring thoughts.

I saw one of the chess.com moderators mention in the Live Chess lobby that tigerpetrosian was in fact found to be using a program.
Who is the highest rated person on chess.com?