Anyway, I just finished. In some ways, it's incredible, but in others, it frustrates the hell out of me, and I hate it. I guess it says a lot about the game's accomplishments that I stuck through it even after I had failed over 150 missions.
The world itself is amazing. There isn't much in the city to interact with, but it's so huge, and I think I'm going to like exploring it for a while now that I'm finished with the story. But I really hated the mission design, for the most part. The game teaches you to take cover behind walls, etc, and then all of a sudden someone will jump right in front of you, or shoot you, despite you being completely hidden by the wall. Or an enemy might sneak up behind you from off camera. I don't think the game's controls work very well at all in those situations.
And I think one of the biggest problems is that there are missions where you need to do things in a very specific manner, but you aren't given very specific instructions. In the scripted chase sequences, you should be following a certain distance behind... often, the enemies could damage you, but you can't damage them. So, if you follow too close, you'll be killed. But how would a player know that they shouldn't attempt to kill the enemy? It just doesn't make sense. And the story, well... I thought it got kinda convoluted in a couple points.
If anyone wants to add me to play online at some point, my gamertag is lolwot. I can't play now though.