Not to mention Button won his title by more than a point whereas Hamilton kinda "backed" into his, if it wasn't for Glock sliding wide in Brazil, Massa would be holding the title and Hammy would be just another contender. You know that's gotta be on his mind. Vettel barely won his first title but dominated for his second and Hammy will be holding a solid 5th in the Championship standings.
Now as much as I dislike Hamilton as a F1 racer, he did well to promote himself as a likeable guy in the Seat Swap with Tony Stewart. He seemed genuinely stoked to be ripping around in a stock car.