Last season I enjoyed was Season 10. I thought season 11 might be good when they started with the Mel Gibson episode, but the following four episodes (Ritalin, Food Critic, the first bad ToH I can remember, and Tomacco) began my cynicism towards the show
There have been a couple episodes here and there they I intermittenly enjoyed, like the boy group parody or the Run Lola Run parody, but now, for the most part, when I occasionally tune in out of curiousity, I'll wind up sitting through the episode with a straight face (as I did last night)