I just picked this up Thursday and I'm around 13 hours in and I am just loving the crap out of it. It has great graphics, art design, voice acting, smooth frame rates, awesome story and is very hard to stop playing. Didn't think I would be liking it as much as I am but it's turning out to be one of the best games I have played.
I downloaded and played the demo of the game, which is the entire first level. At first I had little interest in the game, but then people compared it to Soul Reaver which is my favorite game series ever made. I really liked the demo, but I'm probably going to wait until it goes down in price before buying.
And I think it's really cool they released such a big demo. Most of the time, demos last about 20 minutes, but this one took at least an hour
I rented it and loved it. If that game were on the "Greatest Hits" list it would be sitting on my shelf right now.