Don't get me wrong,
I'm not saying the game itself is bad. I'm just saying that the high pedigree of games that came out this year means that even the slightest issue or bug could potentially remove a game from being considered for game of the year. Such was the case, in my opinion, with Little Big Planet, which, despite its innovative design and pleasing aesthetic, had issues that one must consider when comparing it to other quality games.
I liked it, I think its fun, but its not necessarily the type of game I would have considered "Game of the Year" material. Not bad, just not the best.
Begin Rant
Although personally (if we want to go there) I have been known to refer to the game as "the most delightful and whimsical level editor you'll ever play, though I think its a stretch to refer to it as a game." LBP is endearing at first, but once you get into the core of the game you realize that all the things which turn what is essentially a level creation tool into a 'game' are cumbersome and inelegant. Before too long you're wishing you could just use a mouse and keyboard instead of having to slog through LBP's interface to make simple objects. I think the creation tool that is Little Big Planet is hindered by the fact that you have to play it like a game, and I think that's reflected in the vast majority of user output. It takes too long to make anything good, and unless you're getting paid to do it nobody in their right mind would take the time to make anything beyond the simplest of levels. I, of course, am not in my right mind, so I am willing to put in the time to create something I'm proud of, but I still question Media Molecule's choice in making a game for crazy people like me, and even though we are willing to overlook its many profound problems, we are very aware of the game's limitations.