well, i thought that the game was fairly well done. i like the changes to the control scheme which helped to simplify the game a bit while adding some depth at the same time (Xbox 360 version, here). combat in particular was much more fluid as enemies seemed to actually want to attack you at will instead of waiting for you to counter them all the time. the tree running in particular was a nice touch, and after some practice, its not really all that hard to get Conner running in the right direction (although its still not perfect).
and the naval missions?? spectacular. i'm a big fan of that time period, and i'd have to say that if they had done a game without the naval missions, the game just wouldn't have fit the period very well. this was the apex of the Age of Sail, and to not include at least something similar would've been a huge disappointment. my only complaint is that it doesn't really suit Conner to have been a privateer captain. i thought that they could've worked the story around so that Conner was driven from the northern Colonies and forced to become more of a pirate captain so that he could force his way back in, but its a minor issue at best.
my last thing to note is also my biggest complaint with the game. why does everyone in the game have this whole "good intentions/bad execution" thing going on? Sam Adams is very idealistic, but omg he owns a slave!! Washington is a strong leader and a charismatic example of what the Revolution stands for, but he attacks and burns "helpless" indian tribes (nevermind the fact that they were actively aiding the British). the point that i'm making is that the game seems to be obviously written to magnify their flaws. they make them out to be power hungry with no real intention other than the benefit of themselves, and that they're not all that different than the Templars themselves. from a writing perspective, its a good idea, but it makes the historical aspect more of a backdrop than the reality the game is trying to portray.
in the end the game is a lot of fun. i think that i enjoyed Assassin's Creed 2 a bit more, though, and the game has quite a few flaws in the design and writing departments. just remember, though, that even though a game isn't GotY material doesn't mean that its a bad game. this is a good one that fits into the series rather nicely, and its definitely worth playing.
See the struggle of the faithless lot as they negate their time
How low to sink to the depths of their frame of mind