My concern is repetition. 1:1 sword fighting is cool, but will get boring quick unless you have to use skill, brains and reflexes. Even then, it'll get tiring before long.
So I'll be very interested to see how they keep it fresh throughout the game.
Also I worry that reviewers may hate the game, because they tend to play games for 10-12 hours straight to do a review and 10-12 hours of continuous sword swinging and the arm craps and charly-horses that come with it won't be enjoyable for anyone.