Okay, let's start from the beginning.
Graphics: Amazing. The first cutscene that the demo starts with has absolutely amazing animation all done via performance capture, ridiculous skin texturing, high polygonal detail and some really nice lighting. The game basically carries this throughout the demo, which is only like 10 minutes long. The lighting in this game is really impressive, and thanks to HS's colorspace converter, has HDR and AA. Not a jaggie in this game. Really, really impressive. The combat animation is so freaking fun to watch. You have really nice, short animations for all your regular moves, but when you hit a Perfect Counter or a Superstyle move, you're in for a ride. There is a bit of tearing. Framerate seemed pretty consistent to me...didn't notice a drop, but I'm not the best at that. Really nice special effects like sparks (lol) and also the way barrels break apart when you throw them. Some of the shadows in the cutscenes shimmer if that bothers you. I didn't think it was that bad at all.
Controls: Seem really nice and fluid. Very spot on. Throwing shit with the sixaxis is so fun. You've got two attacks like in GoW, the counter, and the three stances. I found it really interesting to switch up my attacks and counter a lot. The ranged stance is really fun for button mashing because it just looks absolutely spectacular. You can just press square and watch as Nariko goes to town. I found the response on the regular stance to be spot on and the response on the power stance to be a little delayed, as I would expect.
Combat: If you like God of War, you will LOVE this. It takes the best elements from that (animation, visceral combat) and mixes them with my favorite thing from the "grown up" combat games-- counters. It's so fun right now to mix and match and counter. You can probably get by with just mashing square, but when I tried that I found it really difficult actually. Enemies were consistently blocking and it was impossible to beat the first tough enemy that way (fail the last part of the QTE). Hitting a perfect counter results in a kill with a decadently beautiful animation. It usually involves Nariko stepping on someone's nuts or slicing them in the nuts. Nuts lovers beware. The power stance was pretty effective in taking care of the losers that were excessively blocking. I thought it was a little difficult even, as I said. I was attacking on the first pillar for a few minutes and not everybody was dead, so I was impressed. I really think this is pretty fun and satisfying. No, it's not as deep as Ninja Gaiden and yes, you probably can button mash if you want. If you do, it won't be fun. If you exploit the counters and stuff, this game's combat becomes pure fun visual masturbation with some fantastic payoffs.
Music: This is the part that kind of took me by surprise. It's stunning. It's excellent. The music in the trailer that plays if you just let it loop is amazing, and the title screen music is also beautifully composed and performed. I think there might be a glitch with music dropping out of cutscenes and QTEs. I'm not sure, I can't consistently recreate it. The sound effects are all absolutely awesome. Lots of chains clanking and swords striking balls.
Ask me questions and I will do my best to answer. I'm going to play again.