I'm not particularly sold on Luck either. People are claiming Luck is the second coming of Peyton, but if anything, he's a Peyton Lite. Just look at what he's done in his college career and compare it to Peyton. Peyton makes him look silly.
There are some players you can just watch play, listen to talk, or just get a general vibe off of even without ever meeting them in person, that makes you say "ya, that's a bad, bad man." Peyton is one of them. Luck? I don't know, I'm not feeling it from him you know?
As for the future of Peyton with the Colts, I say the Colts can't trade him because they basically can't. If they absolutely wanted to/had to they could, but the problem is all about time and money. If the Colts were to trade him, they couldn't do it until the beginning of the new league year in 2012. However, Peyton is due another $28 million before the new league year even starts. So regardless of whether or not they want to trade him, he's getting that cash (unless the Colts cut him). Not only that, but if the Colts decide they absolutely want to trade him, they will not only take that $28 million hit, but they'll also be on the hook for a cap hit of $38.8 million. Combine the two numbers and you get a total of $66.8 million dollars down the tubes just to trade him. And who knows what his market value would be, especially with the contract he has.
Let's just hypothetically say that the Colts could get two first and two second round picks for him, would that even be remotely close in value to $68.8 million? I don't think so. So I think in order to prevent a collapse of the franchise financially and to maintain high popularity with the fanbase in the future, they just can't take such a risk like that. Not only that, but how on earth could Jim Irsay and the Colts FO show themselves in public or talk in an interview or at a press conference after having just traded the greatest player in franchise history, a player that made the franchise, and arguably the greatest player in NFL history? That's like business suicide you know?
Basically what it all boils down to is this: If Peyton is healthy, he's going to retire a Colt. If he isn't, he's going to get cut and the Colts will draft Luck and pray to the heavens he is the next Peyton Manning and not Ryan Leaf. What the Colts will do with the first pick if they do keep Peyton is beyond me honestly. I personally would trade the pick and load up for 3-4 year sprint to the end of Peyton's career and hopefully win a stockpile of Lombardi trophies.