I tried the demo out today too. Like you mentioned a lot of action oriented gamers will be turned off by this game.
I actually enjoyed the demo really well. the controls (walking in particular) was a bit awkward. However the developers have captured moody atmosphere which suits the game just so perfectly! This game should get a rating of around 8 or 9 out of 10 judging by initial reviews done by some small time reviewers.
Graphics were really good, but i wouldnt bet on it being better than Uncharted 2 (can my SDTV be blamed for this?

). The game will definitely have some replay value (at least 2 tries) judging by the demo.
Really looking forward to the reviews as a purchase 'maybe' in store for me.