Oooh, shiny orbs...
In crackdown, you play as an ultra silent and glowing object addicted super police officer, who has been let loose to clean up a city full of racial minorities that need quelling A.K.A. gangs. These gangs have certain key members that you can take out, and this weakens certain aspects of the gang, such as if you take out the weapons dealer, the gang cannot source stronger weapons for its thugs. This leads to some interesting opportunities, but in the end the actual "story" part of this game isn't that overwhelming, due to shallow enemy AI, a fairly busted aiming system (wait patiently whilst your aiming reticle shrinks and allows you to shoot long distance with a pistol), and a mildly un-nerving undertone of "hey better get the asians, 'cause their the biggest bad guys, and all speak like kung fu masters from bad 80's movies."
But this isn't why you play Crackdown. The superhuman abilities your character have also have an addicting component to them, which is the collection of orbs. These orbs are gained from doing such tasks as shooting enemies, completing races, and climbing to high heights. This collection of orbs is a very rewarding experience, since you can noticebly see your character get stronger as he beats up more people, and you jump higher as you get more agility orbs. These agility orbs are the most addictive part of the aforementioned orb system, since you can see and hear them everywhere, so that eventually you just snap and go "HOW THE HELL DO I GET UP THERE!" This then forces you to get quite creative and find the minutia of climbing these buildings, and has a really good pay-off, with your character getting progressively faster and higher in his jumps and movements.
These orbs, combined with the fact that your powers, especially after being leveled up, are just plain fun to use in the game. This is even more so when you play co-op with a friend, and really start wrecking havoc in the game. YOu can also participate in car and rooftop races, and generally just dare eachother to do things like how long can you both keep a body flying in the air.
This game is very good at encouraging its free-form nature, but doesn't do enough with it main singleplayer campaign to warrant a feeling of this game being something truly great or revolutionary, but its still worth the price of admission, just to get those damn orbs that won't stop mocking me up on their high pedestals.