Better action and visuals, but lacking in story.
Marvel sought to pave the road to "The Avengers" (2012), and they hired Louis Leterrier, who'd directed "Unleashed" (2005), "Clash of the Titans" (2010), and the first two "Transporter" films (2002/2005) to take on this avenger. So basically they didn't make the right choice, or maybe they did seeing as those films are shallow in plot and execution, and so was the story for this film provided by Zak Penn, with help from Edward Norton. Interestingly enough, he came up with the story for "X2" (2003) which was far more complex, and better for it. So with a whole universe of hulk comics to draw upon--or more specifically a whole world of iterations of Bruce Banner--then it was interesting that this story was so shallow in plot and character development.
Edward Norton was properly cast as physicist Bruce Banner, whose freak lab accident resulted with a mutation fueled by an almost blind rage. I've always been a fan of Norton, and he made Banner more interesting than Bana did, but only to a point as he was given limited material to work with. As for Banner's girlfriend Betty (Liv Tyler) and her father General Ross (William Hurt), they serve the exact same purpose as they did in Ang Lee's film, and bring the same bad story along with it, being the girlfriend trying to stop her father from completing his mission to kill or capture the hulk without providing any real solutions to Banner's plight. Except without Banner's father in the mix, you're missing a whole section of would be character development and good drama.
So instead they substituted him for aged Royal Marine Commando Emil Blonsky (Tim Roth) whom for no real good reason has a seething hatred for Banner. The bad explanation is that he craves to be on top of his game again, and he idiotically believes that having the ability to turn into a savage green rage monster is just the ticket. So needless to say, he was a real pathetic character who turned into an even worse villain. But again, similar to Norton, Roth makes the character tolerable.
The action and visuals were vastly improved upon from Ang Lee's film, but again, they become the story, but don't tell the story like they do in the "Mission: Impossible" franchise. They just serve as story breaks, and given the severe lack of story or character development, then that's not much of a break so much as a neat execution of action sequences fans of the character really want to see. Maybe they really liked hearing Lou Ferrigno's voice? Besides his cameo, he voiced the hulk here, and that put a smile on my face, but I'm not sure why. I just found it funny. And ironically, the best action scene in its execution and location is when Banner is fleeing from the military in Lima, Peru. Great cinematography with several jump cuts and choreography to match the lightning pace of close quarters combat made for an excellent chase scene. But sadly that's near the beginning of the film, so there wasn't much else to look forward to.
Overall, the idea of what the hulk is makes for just that, a neat idea. It doesn't really work in a 112 minute film, let alone a 138 minute film without some subplot or character development to carry us along. For as shocking as this obviously is to Banner, we'd expect to see multiple angles to his psychological transformation of accepting who he's become rather than a mad dog international chase to find an answer, which by definition we know he won't get, since he must still be the hulk come time to join the avengers. Not to mention, this is an origin story, so why not focus on his mental journey while you're going on this wild goose chase rather than just focusing on the action and one angle of his mental state?