Considering that football is all he has ever done (aside from endorsements) I say good for him. If he can still play and loves to do so, why not? It is normally a short lived career .... make hay while the sun shines applies here as well.
I think he truly has a love for the game. He loves to play. You do not have to be old to get hurt in football, but the older you are your odds go up.
I am a Farve fan, I think he is a great QB,person, and player. I am not a big fan of all the drama. I wonder how he would be as an QB coach, or up in the booth? I really do not think the money matters to him. He has lots of ways of making more money than any of us.
Oh I have no doubt that once he does hang up his jersey for good he will end up on ESPN or FOX as a sports announcer. QB coach is another possibility because there have been several REALLY good QBs that were his backup that i am sure learned a lot from just playing under him...