It lives up to it's name. That is to say, the Hulk is in it, and he destroys a lot of stuff.
Here's the key items that I think impact the game-play the most.
The Hulk: He's in it; a must for Hulk fans. He's big, tough, and represented quite well I think (of course I'm admittedly not a Hulk aficionado). The game also makes sure that you play only as the Hulk. I'm sure it may have been interesting to have you play as Bruce Banner, maybe in a couple of stealth levels or something like that. At the same time, I don't think it would've been worth the variety, since people who buy a game with a name like this probably want to play as the Hulk as much as they can.
Damageables - You can pick up people, lamp posts, trees, concrete road barriers, cars, buses, and pretty much anything equal in size to or smaller than a tank or small mech suit, and use it as a weapon. You don't have to look hard to find something you can pick up and throw. Most vehicles will also show visible damage as you pound on them. Streets will crack when you land on them after a high jump. Bricks and concrete will crumble off buildings as you run up the sides of them. All very nice. Sadly, it's the larger mechs that disappoint in the visible damage arena. Sure, they'll light on fire, but I never really noticed much actual damage on them until they're about to explode. You kind of lose that sense of power you're suppose to have when your charged up flying fist attack doesn't even put a dent in the armor.
Side Tasks: There's plenty to choose from, and some of them are quite fun. One kind in particular has you searching the rooftop for soldiers with rocket launchers, and you have to take them out before time runs out. More often than not though, the bonus missions are more like mini-games. Some players may get a kick out of them, but somehow giant-inflatable-gorilla-sailing didn't seem to fit in with the rest of the game-play.
Camera: It's not great. It works best when your target is a few blocks away, and in front of you. When you get into close combat situations, you can lose sight of your target and lose sight of yourself. During some the more hectic scenes in the second have of the game, the busy scenes can cause confusion as to what's going on. In these tight situation, you just use the lock-on feature, mash the buttons, and hope you hit something.
Controls : Like the Hulk himself, they lack finesse. The lack of responsiveness can make it too hard to pull off precise moves, or change tactics in the middle of an action or combo.
Upgrades: Probably the best part of the game for me, there's plenty of new moves to unlock and purchase with the smash points you collect throughout the game. With new moves come greater damage potential. Despite the number of upgrades that are available, the ones you acquired early on get redundant as you progress through the game and the average foe you face gets bigger and tougher. Of course you won't mind using the heavy moves when it includes things like throwing a tank or using a bus as a skateboard before you throw it like a boomerang. The trouble with the heavy attacks though, is that they require a couple seconds to charge up. This is a problem when you're trying to take out a large enemy quickly, however the constant barrage of rockets that are raining down on you don't provide you with the 2 seconds you need to charge the attack. Of course not all of your upgrades are on the offensive. You can also upgrade the Hulk's health, and unlock defensive moves which will allow you to use large vehicles as a shield, or knock away an incoming missile (when timed correctly).
After you've played through the story missions, and tire of the bonus objectives you can just run around the environment causing havoc, and raising your "threat level" until the authorities feel the need to try and put a stop to your destruction, and start throwing random bad guys at you.
Looking back, it's the kind of fun that can probably best be described as "Weeeee!". Nothing serious and holds some entertainment, but wasn't overly memorable with a few frustrating battles thrown in the mix. It's worth a look if you're into super hero games, and it's probably a must have if you're a Hulk fan.