Ok to begin this is the first assassins creed but it is bigger and better in just about everyway, the ground rules are essentially the same as the first but little tweaks just make it that much better. To begin, I will discuss the gameplay. This is much more open and free than in the first assassins creed, in the first it was gather information in a very limited number of ways then kill somebody, this time it is much more open with an increased number of mission types. The stealth mechanics are very clever allowing you to manipulate crowds for example by throwing money to move the crowd or by shoving people in it. The free running is much the same but I can't complain as I thought it was brilliant in the first game. The combat system is much the same with a few little added touches e.g. stealing enemy weapons to use against them. There is also the addition of money which was missing from the first game, this enables you to purchase all kinds of weapons and armours, just adds another nice little touch. One of the best additions is the addition of the ability to swim, which as anyone who played the first one knows that when free running drowning really ruins the feel. Graphically its better than the first which I find surprising as assassins creed 1 was very good graphically, but this just steps it up further making the game again more to enjoy. Although great graphics comes at a price apparently with drops in the framerates when there is a lot happening on the screen at that moment. The achievements aren't for annoying things like finding 100's of flags they are just for things that could actually happen in gameplay eg. Spend X amount of money here. The story is longer than the original also taking me around 15 hours to complete the main quests and is better with some very nice cut-scenes driving then game along.
Overall I would definitely recommend it to anybody because the numerous little improvements add up to a massive jump in quality and the frame rate issues are not a cause for concern when the rest is this good.