At least one man involved with Marvel's movies isn't down with the much-rumored idea of making Bruce Banner's alter-ego the reason why the The Avengers form. Incredible Hulk director Louis Leterrier calls the idea "too simplistic".
Talking to MTV, Leterrier said that he'd rather any Hulk-villainy wasn't his own fault:
What's great about Marvel is that it's never good guy and bad guy, hero and villain - it's more complex than that. Hulk could be in trouble and chased by Iron Man, no problem. But I don't think he would end up the villain, killing people and being villainous of his own free will.... In the Avengers stories when he was the villain, he was always controlled by Loki or someone else, and it was never of his own doing.
But even if Bruce Banner ends up the bad guy, Leterrier is still excited about the potential of 2012's Avengers movie:
The next step in superhero movies is the clash of cultures. That's what's going to be so fun. 'Iron Man' was great, but you don't remember 'Iron Man' for the fantastic action sequences - though they were great - it's the human interaction and how great the human actors were... When you put Thor in Tony Stark's universe, it's fantastic. Then you add the anti-superhero that is Hulk, who's like, 'Leave me alone, I don't want to be a superhero,' and you tell him, 'You have to come with us or you have to fight us,' and then on top of all this you have Captain America, a gung-ho super-soldier who starts doubting himself and his system... and that's fantastic. You have all these interactions, and that's just the beginning.
Fantastic? No, that's the Marvel characters that're locked up in a Fox contract...