My opinion is that he might be a bit soft and not the same type of competitor as a Brady or Dion or hell even a Sherman who took a deal that isn't as guaranteed as it looks to stay with a winning team. He got owned by Steve Smith against the Ravens and didn't even bother competing after the ref picked him for a half second in the Super Bowl.
Striving for true greatness and back to back rings might not be what drives him, he might just have wanted a single ring to validate his career and go back to NY where he can be the star and get to vacation in January. Although, I think this past year may have changed him.
I hope I'm wrong and that he resigns, he is a great player and I loved having him here for this past year and thank him for his contribution to last years team.