The Titans. I went to school in Nashville from '97-'00, which includes their painfully close loss to Warner's Rams in the Super Bowl. Those are good football fans, and for a relatively small NFL market it is a great football town. I also think it would mean more to those fans than any other fanbase out there. Sure, the Steelers fan base is probably the most rabid bunch remaining, but they've tasted their fair share of glory.
I really don't want to see the Ravens win it, and not just because they beat the Dolphins (though sour grapes is part of it). I can't stand the attitude of that team. Their defense is truly great, I'll give them their due. But that makes their cheap shots, taunting, etc. even worse because it is wholly unnecessary when their play speaks so loudly. I know they want to intimidate, but that's just not a style I can get behind. Plus, anyone remember fat Siragusa rolling around on top of Marino trying to injure him?