Other people have said that Assassin's Creed was an exercise in repetitive gameplay. And they were right.
The game also starts to set up a big story. Though, I feel, and have cited in other reviews, that in action games or first person shooters, the story is usually only as good as the gameplay.
And, unfortunately, after a couple of missions, the gameplay feels tired, uninspired, and repetitive.
All three of these things become painfully noticable, because of how long it takes to move from city to city, and worse, how long it takes to move once you're in the city. It feels like it takes forever to get from one objective to another, and outside of an occasional minigame of 'eavesdrop on this" or "pickpocket that", which also become repetitive, there isn't enough to make the time feel well spent.
While the environments are exceptionally large, and quite breathtaking at times, your ability to interact with the environment is severely limited. It's open ended, in the sense that you can physically explore the towns you enter, but it's not in the sense that you can't communicate with anyone along the way, so nothing is providing any sense of personality, atmosphere, or interactivity to help give weight to the scale of it all.
Which makes the time it takes to get from one objective to another feel even longer than it should. You can't interact with the environment at all, outside of doing repetitive miniquests, which the gameplay forces you to slowly move through, which to me, makes all the space and scope feel useless, and tiresome.
The action system, I feel, had potential. Unfortunately, outside of sneaking by yet another guard unnoticed, or stopping yet another guard from interrogating yet another citizen, the need for an elaborate action system feels unnecessary, except to make you snail crawl through a city that looks and plays just like every other city you've visited. IN combat, things don't liven up that much either, as you basically have a few attacks between all your weapons, and strategy never really changes from foe to foe.
The story is interesting, unfortunately, the environment and the gameplay don't do it any justice at all. If the game had either settled on being a truly open ended game with an interactive environment, or if it settled on being a straight ahead action game that focued more on objectives and combat, I feel either would have served the story better. The first could have opened up the world to you, making it feel more immersive, and the second would have made the story feel more immediate, and intense. The fact that it was not really one or the other, yet tried to be both, compromised both immersion and intensity, and made the story drag where it didn't need to, without offering any significant reason for the amount of time it took to do even simple things.
I thought it was just me, since so many people have liked this game, so I forced myself to play through past the second memory block. After the forth, I kept telling myself that it was all building toward something, so I forced myself to keep going, even though I wasn't really enjoying it. By the end, the gameplay and travel became so tiresome and needlessly lengthy, and the world remained as painfully uninteresting, that when the story finally did flesh out, I didn't really care anymore. I finished only to prove to myself that I had given it a fair chance to be the game I hoped it would become, that other people said it was.
Which is too bad, because if as much thought was placed on the gameplay, as was obviously spent on the premise and overall design, Assassin's Creed could have been that game for me.
Unfortunately, that game never came, and that fact was just as clear to me in the first 30 minutes of playing, as it was when I finally pulled it out of my 360's DVD tray, the only difference upon completion was that I realized I could have spent my time playing something else that would have been far more enjoyable.