I just finished this, and i was questioning it being on the game of the year lists, but it definitly deserves it. The combat looked too simple and the hiding on gargoyls looked too easy during the demo but the full game completely proved me wrong.
I also couldnt put the game down. Luckily I rented it since I usually stop myself from beating games I buy too quickly, so I had no problem just doing the story as much as I wanted.