Must be Game of the Year!
Graphics: 10/10
God of War III has the best graphics on the Playstation3, which are a little better than the newly released FFXIII. Perfectly detailed animations, Kratos is filled with blood when killing a victim and generaly the graphics are going to impress you VERY much.
Gameplay: 10/10
In the new God of War, the gameplay is like a combination of the first two God of War games. More or less, if you liked the first two God of war game's gameplay, the new game is just going to impress you much more.
Story: 10/10
I WON'T SPOIL ANYTHING. The story is just going to leave you with open mouth. For sure.
To conclude, the game is truly amazing. It is worth buying it and in my opinion, if you don't have it or if you haven't tried any God of War game before, you surely must buy this game.