Well, they have the number one draft pick now, so this may be a sign they are moving on, and Peyton will be traded. It could be that they have an opinion from a team or consulting doctor that Peyton probably will have to hang it up, for all we know.
I think Peyton has 2-3 good years left at least and that this might be a mistake. I guess we will find out.
IMO, if they think they can get another 2-3 years out of Manning, then they should trade down, stock up on picks, and build around him for one more Super Bowl run. But you have to take Luck unless you're absolutely positive that Manning is good to go, which they probably won't be by draft day.