Personally, I find the best way to avoid spoilers once a game has been released and I don't have it yet is to simply avoid the thread :p
Did it for Mario Galaxy, did it for Bioshock, did it for Mass Effect.
Managed to get through all of them without spoilers. While it will be a shame to have to do it for so long due to us having quite a wait for release, in my opinion it will be worth it.