Crackdown adds some solid ideas to the sandbox genre but doesn't execute other standard ones well.
The game is short and can probably be beaten within 4-6 hours. All you do is travel the massive city until an incoming transmission comes which makes you go hunt for a baddie. This gets repetitive - fast.
Has jumping around ever been so fun in a game? Probably not. In the game there are 500 agility orbs that will make your character jump higher and farther. Doesn't sound too interesting or fun but it actually is. Seeing how high you can fully jump when maxed out and jumping and climbing huge skyscrapers make Crackdown's agility orbs a very fascinating concept. Because of the jumping and running around being so entertaining and well done there has to be a downside. That downside comes with the driving. It feels slow and just not fun at all. At times I thought to myself - should I choose the car or just walk there and I always felt like jumping and climbing.
Crackdown also adds another feature to online sandbox games - co-op! As I recall, because its been awhile since I've played the game, you can only play co-op through X-box Live. You might be thinking not another Saints Row horribly done 'co-op" modes but its not like Saints Row at all. You and a friend are thrown into the same huge world as the single player adventure. Also, you can play the entire game in co-op. Co-op I found made up for a lot of the negative parts of the game. Since you are playing with a friend you can just have fun. Personally, I found it very entertaining to go through the Stunt Rings with a friend which made it easier and at times very entertaining.
Usually I wouldn't talk about the achievements in a review for too long but for Crackdown I have to. Crackdown is one of the few games that does the achievements perfectly. Even after a short and boring storyline there is so much to do because the achievements make you run around and do fun things. The achievements also gives the game a bigger lifespan. Countless hours I wasted away collecting all the orbs and going through all the stunt rings.
When you first put in Crackdown don't have huge expectations. Don't think its a next gen Grand Theft Auto because truthfully its not. It takes a different spin on the usual sandbox gaming unlike Saints Row which is exactly like Grand Theft Auto.