Director Joss Whedon is still finishing up The Avengers for its May 4 release, but already he's bravely presuming that Marvel might have an interest in making more of these things. He's also presuming Marvel would be cool with an Avengers sequel being "smaller [and] more painful," which does not sound like a tagline Marvel would approve of.
"By not trying to. By being smaller. More personal, more painful... By being the next thing that should happen to these characters, and not just a rehash of what seemed to work the first time. By having a theme that is completely fresh and organic to itself."
So what he's saying is that a film with two Norse Gods, a man in a metal suit, a babe in a leather jumpsuit, Samuel L. Jackson, bow-and-arrow guy, a huge green monster in pants, a patriotic shield-bearer from the past, and a group of some kind of flying aliens does not need to be any larger? It's a fairly convincing argument, Whedon, but I'm curious how it will fare against Marvel's superhero masterplan of amassing a custodian's keychain of the biggest, brightest, shiniest things guaranteed to grab our attention when jingled in front us. "Small, personal, and painful" sounds mature and all, guy, but Marvel would really like to sell some stuff to some ten-year-olds and manchildren, don't forget.
On that point, here's an interview of Whedon talking to Empire about why the Iron Man suit in the trailer no longer has the triangular arc reactor from Iron Man 2. In short, he thinks "the triangle is ass," and even if he'd kept the triangle, you wouldn't see it long anyway: in the spirit of Iron Man 2 and Marvel wanting to have a bunch of variants to sell as toys, there are going to be all sorts of suits worn and Battle Damaged™.
So there you go.