Grand Theft Auto IV is one of the best games to come out this generation so far.  It's open world nature, tight story, and great characterization combined with tried and true game play make it a favorite of mature gamers.  If the sales numbers of the recent downloadable episode, The Lost and the Damned,  are any indication - no matter what format you put this game on people will eat it up.

One problem though with the game is it's lack of a true co-op mode, instead GTA came with three simple co-op missions with limited replay-ability.  The Lost and the Damned didn't add any new co-op content, which was very disappointing.  With one more exclusive episode on the way to the Xbox 360, IGN (and Us) hope to see some true co-op finally.