I just fired up Assassin's Creed 2 and let it idle, which I haven't done before. The idle movie that played involved Ezio chasing down a man during the festival in Venice, cornering him in an alley, and then shooting him with the gun attachment to the hidden blade - upgrades that I just recently unlocked in my save.
"Cool!", I thought, "it's giving me a recap of what I just did in-game!" But then it occurred to me that maybe there's only one movie and they simply chose to show off some of the more neato-sweeto tools of the assassin's trade.
Does the Assassin's Creed 2 opening cinematic change based on how much of the game you've completed?