I'm enjoying inFAMOUS because it combines two of my favorite things. Like Mirror's Edge, you can run around on rooftops and listen to fox news tell you of a government consipracy. But you also have the open-world fun like Fallout 3, where you run around killing people while a visible morality index keeps track of whether the angel or the devil is suggesting your targets.
I guess it's Grand Theft Auto with electrically-charged superpowers, because when you get tired of the story line, you wander around discovering side-quests, and when you're tired of side quests, you hop back on the main storyline.
There are hours and hours of gameplay in here! And the comic-book styling of the HUD and the cutscenes and things are very pretty. Go get a copy!