I know it will only be a huge beta test this year but Littlebigplanet is one game that would keep me entertained for months. There is so much to this game, listening to several reports on the game you could make a Sackman football game or a driving game, let alone all the platform games, it would be possible to make a 2d shoot-em-up using the Characters from Halo if you so wished. This game will be immense in so many ways, I just cant wait to play it, will find out more about the enemies and giant bosses in the game at TGS (Giant Enemy Crabs anyone?)