Assassins Creed is one of those rare and innovative ideas, one not previously expressed in many other games.
First of all, once you know how to play and the strategy involved in defeating heavily armored enemy's with more experience than you it becomes a rather easy game. That said, it is action packed and addicting to play, and there's will always be some sort of challenge especially deeper into the game.
Graphics wise, I have little complaint besides the faces are more of the style from older generation games, what with the at times over exaggerated features and the heavily contrasting features, but that is only close up, namely in previews.
Now the game-play issues. These are the issues that people will use as a main argument if they don't like the game, often stretching the truth to suit their needs. First up, most of the game is spent investigating and then assassinating your victims, then again that's why it's called "Assassins creed" duh. But the repetitive nature can get a little boring, but trust me persevere and it will get better, and namely more challenging. I particularly enjoyed the ending, but no spoilers there. Most people say, and I guess I agree, it could have used a little more "oompth" so to speak. More freedom and more things to do isn't too much to ask for.
Anyway now to sum up the good and great of the game:
The controls are easy to learn but hard to truly master, which adds challenge figuring out the best way to assassinate and best way to win against multiple opponents.
The graphics as a whole, even now, impress me.
The idea of accessing your ancestors dreams from a strange machine is completely original, something all too rare.
The game is fun to play!