I'm only 7% through the game, but it's better than I expected (and I expected quite a bit with all the hype). I'm not a huge gamer, due to time to play, but I own all the AC games, having only completed the first one (with 'someday' plans to finish the rest). This one, however, I'm making time for. Loving the story line, and sailing the ships (and battling with ships) is much better than I anticipated. Plus, I keep hearing from friends that it gets better further into the game. Being a casual gamer, games rarely 'hook' me, but this one has managed to do just that. It makes me want to go back and complete the entire series, after I've finished this one, to see what I've missed.
Story-mode is flawless. Ship battles were perfectly incorporated into the game to give this game the edge it needed over previous releases. Online multiplayer is also very fun, although it gets pretty repetitive when trying to grind levels. Only thing I don't like about the game is the weird cut-scenes that show you as an employee for a company that is analyzing how you're playing your game. I didn't get what they were trying to do with this. They should've just left this part out. Besides that, superb game.
I have played all the major releases in the Assassin's creed franchise and this one is by far my favorite, being that it was on next gen systems did help of course.
The story, the setting, the beautiful locals, the amazing ship combat. Everything was top notch.
I could not stop playing this game and did not stop until I got 100% of everything in single player done Side missions, Collectables, Fully Synced and Abstergo Challenges.