Anyway, back to the point. I loved AC2. I was excited as all get out for the first one when I saw it at PAX '06. Then I played it, and while it was entertaining I agree with the general consensus on it: repetitive to a fault. But that's largely what sequels are for - to improve on latent potential. Anyone remember King's Quest 2? Perfect example. To a large extent, AC2 does a good job of min-maxing Ubisoft's new dynasty. The repetitive missions are largely made optional, your assassination tools are expanded and the world as a whole is much more believable (which is ironic since it all takes place within the Animus). The characters are fleshed-out better, the voice-acting is miles above the first episode, and there are a surprising amount of extra goals to accomplish that help deepen the overarching conspiracy theory on which the plot is built.
My biggest disappointment, on the other hand, has to be the combat system. While it doesn't detract all that much from my overall enjoyment of the game - I know that Ubisoft must have spent a lot of time improving all of the points I referenced above from the original - it has to be said that for a game which revolves around the idea of killing an individual as discreetly as possible, you don't really do much of that. Most of my time inhuming people (extra points if you get the Pratchett reference) was spent surrounded by eight guys counter-killing them one-by-one. And no, my play style didn't consist of charging headlong into guarded palazzos. The fact of the matter is that, at least in my opinion, it's overly difficult to remain incognito long enough to make your assassinations anything resembling a quiet kill.
A big part of that problem is simply that the plot makes you chase a large number of your targets down in public and kill them in front of tons of people. I understand that in the plot context many of the targets generally know that you want to kill them, and that in the circumstances if they see you they'll run away. But the plot -forces- situations where they see you coming. Rather than let you spend a half-hour sneaking around the back of a castle to slip your blade(s) into them, you might, say, have to go 'rescue' an NPC comrade, after which a cut-scene results in you scrambling around trying to air-assassinate them before a timer runs out. I remember in the first Assassin's Creed there was one target that sent you on a city-wide chase, but it made complete sense: he lured you into a trap, stood on high ground gloating, and then hightailed it after you killed all his men and started climbing up after him.
I can only assume that the discrepancy between the two titles is Ubisoft's effort to speed up the pace of the game and distance the series from something like, say, Thief. But personally I feel like there are many fast-paced, run-him-down-and-slaughter-him-in-public games out there, and few games which reward you for skulking in shadows until you have the perfect strike lined up. You can tell me about the crowd mechanism and hired prostitutes, thieves and thugs all you want, but the fact of the matter is that there are less of these groups around for some of the major assassinations than you'd expect, with a few exceptions.
The combat itself is another low note. You feel suitably powerful, considering you can take on pretty much an entire city's worth of guards without breaking a real sweat, but there are some combat options that are so good it's impossible to not use them. Other sites have mentioned counter-kills with the hidden blades, and they're right - when you can do a one-shot kill on almost anything if you time a button press right, why would you use anything else? Especially since like I said, you spend quite a lot of your time fighting large groups. I really miss combo-kills from the first AC, where you could initiate a combo attack and get an instant-kill if you pressed square at the right time after the first attack. Instead the only choreographed kills are the counters and the ones where you've taken the enemy's weapon and they're fighting bare-fisted. It just makes for a system where you have many options, but few -real- options.
I will say that the new types of assassinations - air, ledge, and haystack - are a real treat, and provide a welcome break from silently killing a guard and then either having to drag his body around or risk someone else discovering it. I sincerely hope that Ubisoft makes these truly incognito methods of assassination more prevalent and adds to their number in the next installment.
In spite of its drawbacks, Assassin's Creed has become one of the few series whose future installments I anxiously await, alongside God of War and Mass Effect. I may have gripes about the combat system, but Assassin's Creed 2 more than makes up for it with its fantastic plot, gorgeous settings and memorable characters. Altair merely guided me through the preview; Ezio has drawn back the curtains for the true feature presentation.