@masterkungfu: of course Hulk should be the star but if RDJ or a super popular actor is going to be Ironman then Hulk will lose to Ironman. Even in the avengers movie, only people with good attention to detail could tell that the fight between Hulkbuster and Hulk wasn't a real fight and Ironman didn't actually "win" anything. The majority of people under 18 years old are running around saying Ironman is the best after that movie now. If they're going to make the Hulk scene so complex that only 10-15% of the audience realizes what's actually going on, it isn't worth it.
They're doing a fantastic 4 remake soon which looks terrible.. not sure why every single member of the team looks 15 years old. But I don't think a planet Hulk movie is a good idea as it is just going to embarrass and disrespect the Hulk more than already has been done.