"There are certain standard-setting games in each genre, like the brilliant FPS action of Halo, or the incredible sound design of Bioshock, that you wish could be applied generally to every game you play. Assassin's Creed has its particular perfection - you'll wish that every game had this level of graphics and animation.
When Altair scales the highest points in each ancient city, the view from the top is absolutely breathtaking. Hawks slowly circle your "synchronize" points, where you can take stock of your surroundings and find nearby objectives. Telltale tufts of hay indicate a jumping-off point where you can perform a perfect dive into a haystack.
This climbing, synchronizing, and soaring moments are so strong that the entire game could have been reskinned as mountain-climbing/base-jumping simulation (think Tom Cruise at the beginning of Mission: Impossible 2). But there's just a bit more to Assassin's Creed, like the stealth, crowd, and combat situations."