Great question. I have the 2010 as well, and I was wondering the same thing.
Though I can't answer your question directly, I'm inclined to think that the newer version couldn't be too much different. The format of the MCAT hasn't changed .. (yet). If you theoretically did a large portion of the 2010 book, like I plan to do (never did this for my last MCAT), I can't imagine you being any more well prepared for having had the 2012 ..