Both teams are so impressive offensively, to me, it's going to come down to the turnover battle. Whoever turns the ball over less will win this game.
I think the final score will be 37-27 Colts, with the Colts scoring a late TD to pull ahead. It's going to be a close, competitive game, but I think Peyton's going to make a lot of short throws to thwart the Saints aggressive pass rush. People keep talking about how Indy has no running game. Well, those quick little passes Manning throws more than compensate for that.
If Indy manages to accumulate 100+ yards rushing, then I just don't see how the Saints beat them.
That being said, I would be very happy if the Saints won the Super Bowl as well. The people of New Orleans have been through a lot of adversity, and to win this would be very appropriate for them.
As long as it is a good game, then that's what matters, after all, this is entertainment.