I'd put money down that he'll be a Patriot. He wants to win, has the utmost respect for Belichek, fits into a sideline threat that they haven't been able to adequately fill for quite some time (Mitchell is developing nicely though), they have the cap space, he offers excellent perimeter blocking for their waning run game, and his last few years left would coincide with Brady's. They will lose at least one of their premier TE's this offseason, and he would fill the need for a big target to a T.
With Brady that duo will be scary