I feel kind of ambivalent about this too. I agree with AG that Massa's flashes of brilliance aren't really enough. I find myself wanting him to do better but I'd also like to see someone new have a chance in the Ferrari.
If he can start next season the way he ended this season, he's going to give Ferrari a major headache. As Miggins said, he's been better than Alonso these past few races, they've needed team orders to keep him behind. If Felipe is driving well next season, what do Ferrari do, especially with the Vettel rumours going around.
Barring the team orders scenario and the championship situation, had it been a much earlier race in the year with Massa free to do whatever, does anyone think he would have won Brazil?
I'd argue that Massa was doing a better job than Alonso at the end of the season. Whether that was a genuine upturn of form for Massa or Alonso stumbling is difficult to tell.