I'll try to keep this spoiler free. Don't read if you want to finish the game without the taint of someone else's opinions.

So I finally finished Assassin's Creed 2 and the first thing out of my mouth was "at least I don't have to play that again". Don't get me wrong, I enjoyed the game for the most part but the more I played it, the less I liked it. I felt that they made some good changes but lost some of the things I liked about the first game. For example, the careful planning of each assassination and collection of intelligence was sorely missed.
The game is still repetitive without the bonus of having a reason for completing each task. You perform assassinations for DeMedici without knowing why you are loyal to him. It is almost a "the enemy of my enemy is my friend" type of mentality.
Race events just emphasize how frustrating the free running mechanic is. I would rather see them spend the time to get that right instead of all the wonderful "history lessons" they threw into the game. Yes, the information was interesting but get the core of the game perfected before you add the flavor text. Besides, the race event isn't really interesting and I think should only be used as a tutorial to introduce free running. Just my opinion.
I got no satisfaction from the beat up events. I'm really not sure why they were in the game in the first place. Was it an attempt to show Ezio as a morally good person? He is a man who's main reason to live is revenge. Can he really be bothered to stop a man from cheating on his wife? I mean come on, Italian men are a passionate breed. How can one woman be expected to satisfy such a creature? I guess it's ok for Ezio to spread himself around since he had the decency to not marry any of his lovers.
Part of me has that "gotta catch em all" impulse. I really wanted to collect all the feathers. Not because of some new equipment or achievements to be earned. I truly wanted to make my mother happy. I wanted to help her get through the grieving process. I'd say this is a tribute to how immersive this game is but the fact is I didn't complete that task. It became a tedious task on par with finding the flags in the first game. I just lost interest. And honestly, since we are reliving Ezio's memories, the feathers should show up on the map just like everything else created by the animus. Is consistency too much to ask for?
My biggest gripe came right at the end. In an age where the goal of many games is to immerse the player, why would they do something to completely pull you out of that experience? Credits should roll after the game is done, not during the climactic final scene. I feel cheated to be honest. I wanted to walk away from the game satisfied but my final emotion was anger. I care as much about who made the game as I do about who the dolly grip was in Avatar. It's an egotistical and ignorant move. I appreciate what you do but I will never remember your name and it is unlikely that I will ever meet you. I know one person who works in the industry, that's it. I could have forgiven the rest, at least they were trying to address the problems with the first game. I appreciate the effort, try better next time. This is unforgivable.
Now, it wasn't all bad. I enjoyed most of the puzzles and the conspiracy theory they included. The final puzzle was quite clever. I liked the villa and the idea that you were working toward making your city better and more prosperous. I liked the new weapons, except the gun. And even though I never tried it, I appreciated the introduction of poison. The double hidden blades was quite useful as was the new methods of assassination. And the setting itself was beautiful. Unfortunately, I never ended up liking Ezio. I felt like he was merely a tool and that he was allowing himself to be used by everyone without ever knowing why. I kinda feel the same way about Desmond. I guess we'll learn about that in the next installment. I sincerely hope they get it right, I want to like it.