it was brilliant the way they kept so much humor in it and how the whole movie seemed so organic. unbelievable plot featuring Loki- they really did a great job writing the movie as Loki would scheme a plot. stark's one liners were even better than in iron man 1 and holy crap is mark ruffalo an INCREDIBLE banner and hulk. I thought ed norton did a great job, and I was sad he wasn't coming back, but this couldn't have been better.
so much badass in one film. even as a marvel fanboy and stuff, i can't think of ONE SINGLE thing i didn't like about the movie.
the only things I would have liked better is a burial scene for coulson at the end with all of the avengers present and leaving when captain america walks up to the casket and the camera zooms out as he's walking away and you can see the autographed trading cards.
the second thing is that i wish cap had taken back his earlier comment about tony stark not being a hero. just after he ordered the portal closed, assuming iron man had sacrificed himself (which he, for all intents and purposes, did- he was passed out before he even started falling back down through the portal) to save the planet, cap should have said "i was wrong tony stark...you are a hero".
the very last thing is related to this...where was the gravity that caused iron man to fall back through the portal? maybe there was some sort of pressure change that created a draft that had enough force to seem like gravity. dunno. minor detail that actually doesn't bother me because of the complexity and unknown of wormholes