Just downloaded the demo and I have to say that I agree with the above posts regarding the criticisms. The animations, particularly when players take shots and hit high balls look crap because the players rarely use any back-lift at all! Do EA watch football matches? - when was the last time you saw a footballer strike the ball with no back-lift what-so-ever!?
As stated above, you never really feel entirely in control of your players too.
On the plus side, it is better than previous versions (not difficult to be honest), and the look and texture of the grass and default camera angle are great imo.
Not too sure what people where on about saying the framerate is dodgy because it's rock steady in-game (the replay's still have shite framerates) but other than that it's quite smooth.
All in all, PES 6 has nothing to worry about. That's all it needs to do is play as well as the videos look and it'll still be miles ahead of FIFA (in terms of gameplay of course).
Roll-on the 27th!