Not exactly a great game... but still enjoyable.
Now gameplay first! If you played other GTA's like San Andreas or Liberty City, you'll notice that its just an improvement over combat systems in those games, nothing that can be considered new or original. Now don't get me wrong, the combat system is very good... just for veteran GTA player its... well... same old, same old. The best thing about the gameplay is the multiplayer option, allowing you to unleash massive mayhem upon the city and its inhabitants.
Story is actually quite good. I liked it a lot, since it was actually something that has never been done before, or at least I don't know of any game that has followed a similar idea. The main character is also someone you wouldn't generally see as the main hero. I mean, and eastern European illegal immigrant with a heavy case of depression is not you're regular hero. And I think that the game stand out because of that, since it is something that has not been done before.
Graphics are obviously better than the previous GTA's and judging by the standards when the game was released it's okay. I don't think anyone will complain about the game graphics, as the city does actually feel alive and quite realistic.
So overall? I would say that this game will be awesome to someone who has not played any GTA titles before. But for GTA veterans such as me... it does kinda feel like the same thing again, just with an improved engine and gameplay.