I love just about every aspect of this game. The graphics are smooth with no slow-down and great water and heat effects. You can run through the game back and forth and the bodies of dispatched enemies will still be laying right where they fell.
The sound and voice acting are both good and bring you into the game.
The controls are fairly simple, but choosing which weapons to use or which spells to cast keep the combat from becoming simple button mashing.
You develop your character by giving points to attribute like strength or charisma, by upgrading spells and weapons, adding more powerful armor. PLus, if you finish the game once you can go back through with the same character by importing them into the game and keep building that one character.
Oh, and the game is fun.
Things I wish they had done...sharing between characters when doing co-op (besides dropping an item so the other guy can pick it up)...more npc characters to talk to with more side quests. Not really a lot to gripe about.