Yesterday I played the demo for upcoming EA/Dice parkour game Mirror's Edge. At the time I was impressed but not overwhelmed.
Things they got right:
(1) The controls are intuitive. Left bumper is "go high", left trigger is "go low", and that's all the buttons you'll use 90% of the time. Right bumper is a 180 degree turn, and right trigger is "hit things" which is equally appropriate for punching bad guys and bumping open doors. Face buttons are used for some specific moves including disarming enemies.
(2) Music. Which is gorgeous.
(3) Running. You will actually feel like you're running, not just floating across the environment. There's a real sense of physicality, of momentum, and of speed, which is good when you're generally navigating the environment but becomes awesome once you get some bad guys on your tail.
(4) Graphics are clean, sharp and uncluttered. They look good without getting in the way of your play.
(5) Physics. Faith falls at real-life speeds. That means it's a very short trip from the top of a skyscraper to the bottom, which is nice.
Things that aren't so good:
(1) Anything involving ledges. Shimmying on ledges is painfully slow and badly breaks up the pace, at least in the demo. It feels like this should be about twice as fast.
(2) "Failing" in the tutorial. During the intro level, any time you stuff anything up the game instantly takes you back before you tried. This has two problems; one is that you don't get to see the consequences of your failure. Attempting jumps is only exhilerating when it's understood that stuffing up means falling a really long way. Also the tutorial makes you watch your trainer do each move before you get to do it yourself, and these are effectively unskippable cutscenes you have to watch each time you stuff up.
Things I'm not sure about:
(1) Combat. It felt a little awkward in the demo but you don't get a lot of chances to use it so it may be that I'm just still learning it. It's very timing-based so it's probable that I'll eventually pick up the skill to make it work.
Anyway, having been impressed but not overwhelmed, I've woken up this morning realising that I must have more so I think I'll be buying this when it comes out.