@ajamafalous: I didn't play Revelations, but it sounds like AC3's multiplayer is much like that. I know a lot of the problem with Brotherhood in the beginning was a lack of instruction as to how the game worked, with Targets and Pursuers and the line of sight meter and all that. But they've added a nice, step-by-step tutorial before you play your first match to help new players.
They've added new abilites, changed the way certain mechanics work. It's not radically different, but that's because what's there is pretty solid. You may be right about there not being enough meaningful change for people. And, it's not a game for everyone's taste.