is it even possible to finish AC3? I played like seven hours and the guy that's on the cover WASN'T EVEN BORN YET! how long is this monster? I gave up, that was in December I think. will eventually get back into it, and will likely get AC4. I applaud long games, it's awesome to get that much for our money, but realistically most of us simply don't have the time!
It is about as long as Revelations (25-30 hours). That is including all the side missions. Not the filler rubbish like the 100% memory sync for missions. Which isn't really that long considering you can do that in Skyrim and not even touch the main quest.
AC2 and Brotherhood i found to be longer.