Today, Assassin's Creed IV lead writer Darby McDevitt took to Twitter to answer fan questions via the official Assassin's Creed Twitter account. He was very sure to say that the ending of the new game will be "satisfying."
As I've said before, I was disappointed enough with Assassin's Creed III that I'm taking everything about the next game with a heap of grains of salt. That said, it's nice to see that the man writing the game is confident in its ending. Particularly since he's the guy who wrote Revelations, which had easily the strongest ending of all of the main AC games.