Assassin's Creed 1: side mission, side mission, side mission, assassination, side mission,... end of game.
Assasin's Creed 2: Escape, Street Brawl, side missions, story, murder, escape... Perfect.
Ubisoft really stepped their game up for AC II seeing as some people think that it is the best game of this year. They killed their formula, upped the combat, the story, the missions, everything is just better. The game throws platforming, story, combat, and stealth to create a near perfect game. It was a little glitchy, but it was so much fun. I don't think there was one character that I actually disliked at the end of this game (save the little brother). I beat this, and may beat it again before I think about selling it. The replay value isn't that good, and the game plays until the end, but after a certain point you can just do no more, or you won't want to. It is a great game, and if you have a choice to get this over most other games, this is the way to go.