Peyton Manning may announce as early as this week that he's returning for the 2015 season, according to Chris Mortensen, who writes:
Manning has been fairly persuaded that all will work well between him and new head coach Gary Kubiak, who is ready and willing to fit his scheme to play to the quarterback's strengths.
Well, no kidding. John Elway doesn't fire John Fox without Manning's input, and he also doesn't hire Kubiak if without it, provided he knows Peyton will be back for another year. Yes, Elway and Manning are publicly claiming that Peyton's mind hasn't been made up yet, but the GM surely had a pretty good sense of which way the QB was leaning when he made these franchise-altering decisions.
Per Mort, Manning will undergo a physical sometime between March 1 and the start of the league year, which is March 10. Really, March 9 is the deadline, as that's when Peyton's $19M salary becomes fully guaranteed.