I think where The Hulk will have trouble compared to the other Marvel movies (X-Men, X-2, Spiderman) is just the nature of the character. The Hulk is this huge, gree monster. And, he would have to be done as a digital character to be convincing. As much as Lou Ferigno was cool in the series, this is just a different case.
Here, we're being asked to know the Hulk as he was in the comics. Which if you think about it, is a big stretch for anyone's imagination. You're talking about a 15 foot tall green beast with mega-strength, and the ability to leap miles at a time.
What might have served as a good case for capturing the Hulk's performance is the technique Peter Jackson used to capture Gollum in Lord Of The Rings: The Two Towers. Have an actor try to act these scenes out in a motion capture suit, and then use that performance to drive a digital Hulk. It certainly worked in the case of Gollum.