I think Manning will be done after this year. I didn't think so during the 1st half of the season, but he's been looking pretty shaky the last few weeks. It's like his age has caught up to him in the last couple weeks. I don't think he's going to want to continue playing like that, and it's a bummer.
This also means that any team that can stop the run will probably do pretty well against Denver. It doesn't seem to be as hard to disturb the passing game as it used to be, so stop Anderson and you'll put up a good fight.
If Manning wins the SB, he is certainly done IMO. If they don't make it to the SB, he is also done. If he makes it to the SB and loses, I think he might try it again next year.
Either way, I would be never surprised if he wasn't immediately offered a OC position when he retires.
Next week is going to be for the NFC East. I worry the Cowboys will struggle against Luck and the Colts, but if they make it, they have an offense that is traveling very well. I don't think they can beat GB (Rodgers is just too good for any defense, especially Dallas'), but they have a good chance against a lot of the other teams IMO.