Heck I'll buy it just because the developer is trying something new. I loved the demo but what came through was having combat in place actually felt wrong alongside the free running, etc. I know they probably felt 'action' was required but I felt from demo that if they'd dropped guns (for you) from the mix totally and polished the unarmed combat more that would have worked better with the free running elements.
I love the design look and the actual FPR elements (Fist Person Running anyone) were awesome in the demo. I actually spent more time just playing with how good that was vs the combat elements.
Mind you Assassin's Creed has all the same flaws really - great ideas, graphics, etc. and had a poor story/content... and that still sold well enough.
I wish developers would realize sometimes you don't need guns in every game to sell. Puzzles, running and pure melee would have been far more welcome here.
Try to be reasonable... its easier than you think...
