After a few days of playing it I think I can safely say that I like Assassin's Creed... I just don't love it, and I was trying to. There are a lot of things that I like about it. The control scheme is not too bad, and I appreciate the sentiment of being a bit more forgiving and striking a bit closer to 'do what I mean, not what I press'. I like the idea of adding more of the stealth/tactical killing game play in a sandbox. I like how it looks and I like the conceit of using computer glitches as a visual aesthetic. I certainly like how the menus try to keep from breaking the immersion of the over-story. But amongst all these things I like there seem to be more that I am "putting up with" than I would like.
Perhaps the biggest problem for me is one of "interest inversion", and I noticed this early on at PAX 2 years ago. What I heard from the trailer and the sussurus of opinion didn't really appeal to me... I wasn't really intrigued until I first heard rumor of the backstory, the over-story, the Sci-Fi elements. I still find the Sci-Fi parts of the story more interesting than the assassinations. It's a bit unfortunate that assassinations to me feel like "things to do between pieces of the 'real' story".
Beyond that I've been spoiled in the immersion front by Bioshock recently. Sure Assassin's Creed attempts to immersive, but it is no Bioshock. On the sandbox front I've been spoiled by Crackdown and even to a degree Saint's Row in comparison to Assassin's Creed. I'm not sure if it's the attempted appeal to realism, or what, but for the most part the sections of Assassins' Creed's cities become pretty monotonous. There don't seem to be anywhere near enough landmarks to navigate by and I certainly would have no idea where I was if it weren't for the GPS system. Furthermore the assassinations don't really seem to have anywhere near the replay value of Crackdown or Saint's Rows missions. It's weird because I get the feeling that there are certainly smarter things to attempt than what I try, but I have less impetus to try them. Additionally Crackdown adds additional replay value simply thanks to the ability to play cooperatively across Xbox Live. Sure assassins mostly worked alone, but Assassins' Creed really needs some sort of multi-player and I love coop more than competitive multiplayer.
On that note I find the Arsuf Glitch intriguing. The bug creates an Altair clone when a second controller is plugged in during the load for the last section of the game, that is controlled by the second controller. This does seem a bit too weird to be just a simple bug in the game engine and I certainly have my fingers crossed for some sort of coop play DLC...