4.9/10, even on a post-classic Simpsons scale. This was a real dull opener for Season 21. There are a couple of things to recommend it -- the fact that there's one semi-coherent story for one, and the caricatured but at least true-to-character subplot of Comic Book Guy being true to himself and unable to give his own movie anything other than a crappy review. But for the most part, this is weak broth. There's only the most tepid of satires of Hollywood blockbuster filmmaking and the superhero onslaught that was taking hold when the episode aired, which is a shame since even for a genre I love, it's rife for comedy.
Seth Rogen, who had a hand in writing the episode if I remember correctly, added very little. Rogen himself knows about the "lose weight to play a superhero" game, but the yo-yo dieting bit was all very quick, and Rogen's Hollywood phony character was DOA, with both his cornucopia of nicknames for Homer and his constant two-faced discussions of other clients turning out to be really lame comedy. This one also suffered from the latter-day Simpsons tendency to overexplain jokes or take them one beat too far. Not a lot of laughs in this one, and while the attempt at parody is admirable, it's mostly a big misfire that doesn't really get at the ridiculous of the comic book film industry in any particularly clever way. One to skip.