I finished AC Brotherhood. (You don't have to worry about spoilers while I share my two cents on the ending).
I've read about ppl complaining/upset about the ending, since it was a "cliffhanger" and it didn't give many answers." I think it ended well. How much can they give away? Hold your pants up ppl, AC 3 is definitely coming. Out of all the AC games, I believe the first game's ending was the only clifhanger out of the 3. It had ppl going mad! I went mad. At least with the endings of AC 2 and AC Brotherhood, we knew bits and pieces of where the game would be headed.
For some weird reason I thought that there wasn't going to be an AC 2 after the first, but then in my mind I was like "well, there has to be one since the first game ended like that." I wonder what AC 3 will be like. I wonder if Desmond will be the main protagonist, or if we'll be introduced to another ancestor. I definitely think we'll be meeting someone based on what was said in the ending of Brotherhood.