Great game! Amazing gameplay and story!
You play as Cole Macgrath, a bicycle messenger who is sent to deliver a package for an unknown client. Upon delivery, the package explodes. The effects are devestating-- but not for you. You get super powers. That's where you start making choices. Bad or Good? What do I want to be?
inFamous gives you a huge sense of power. You are the most powerful man in this crumbling city. So you need to decide whether you want to be a hero or villian. When you make a choice, your "karma" becomes more evil or more good. As you make more choices and become more and more evil or heroic, you open up new sets of abilities. These abilities help you to maintain your evil or good karma.
The gameplay in inFamous is top notch. It combines classic super hero combat (punch, kick, etc.) with shooter elements (electric blasts, grenades, missiles), although you'll find that the basic punching and kicking doesn't really cut it when your enemies have automatic rifles and rocket launchers. You can carry out a load of attacks. When fighting, you can string together a bunch of attacks into a nice combo, or just shock someone until they drop over. You can adjust the difficulty, so usually the game isn't very challenging unless you want it to be. The AI is awesome. Enemies actually appear to reason. They scatter when you throw a grenade and get behind cover if they're under fire. The only thing that gets annoying after a while is the movement. Sometimes when you're on the side of a building, you'll try to drop down to the ground, but you just catch yourself on the last window or pipe you were on. And there are minor glitches where you walk through a solid object or can't move because of an invisible obstacle.
The story in inFamous is great, and there are loads of other side missions that you can play to increase in experience. The story lasts a decent amount of time, and there always seems to be something for you to do.
inFamous is an awesome game that anyone with a ps3 should pick up.