Silent Hill Shattered Memories is my favorite game of 2009. That is pretty high praise considering there were some fantastic titles like NSMB, MW2, Batman, Muramasa etc. The thing that put Silent Hill above those titles for me was that it made me think.
It isn't the usual puzzle solving thinking either (although Silent Hill does have some puzzles to give the grey matter a bit of a workout), it was more about the mystery as it unfolded. It wasn't even just while playing the game either, after playing I would find myself still thinking about the mystery and symbolism that is present throught the game. This is probably also due to the atmosphere that the game creates and the psychology involved, which I found very impressive (some questions can get quite personal, to the point of almost making you feel uncomfortable).
I can see why some long term Silent Hill fans would be disapointed that it is a departure from past games. Aside from the loss of combat they'll see changes to characters that don't seem to make much sense. When you finish the game it all makes perfect sense though and actually does fit in with the rest Silent Hill franchise. Now I wont give any details away, but I knew that something was strange when I was about halfway through my 1st play but the ending really is mind blowing and totally unexpected.
As for the length of the game, which is something that seems to be a contention for some people, well it is about the same length as any other Silent Hill game and it does have a lot of replayability due to the different choices and endings that you can get. I'm currently about halfway through my 2nd playthrough and have clocked 14 hours so far. By the time I finish my 2nd and 3rd playthrough (I think you'll need at least 3 to get everything) I can see it being easily over 30 hours.
It is rare to find a game that manages to break out of the cliched genres and that manages to provide a deep meaningful experience but Silent Hill did that for me. If you want to run around blasting monsters with big guns then look to Resident Evil (as that series has turned into a regular action shooter), but if you want something a bit different and that really is a true survival horror game then Silent Hill is currently the best around.