Big mistake if they trade him, he is one of the few players whose performance is worth his antics. They should be realizing that there is no way they can get equal value back, and they will still be paying Manny, screw that, that's just bad business and a poor decision. Right now the Sox control Manny's destiny, use his situation to your advantage and don't act foolishly.
Trading Manny would be giving up on the season and defending the World Series Title, which in a City like Boston is not an option.