After a few days of play on Assassin's Creed 2, I can honestly say that I'm getting extremely frustrated with the free running system. The "free running" gets so clumsy, unpredictable, and buggy at times that it's just laughable, and I think it's gotten a lot worse when compared to the first game. I can't count the number of times that I've jumped off a ledge, while aiming for a wall in front of me, only to have Ezio fall to his doom. And when I repeat the same process the second time, it works perfectly. Also, time trials, and free running are a big no-no.
The climb controls for Uncharted 2 were so simple (and not frustrating), compared to this game.