Well I ran the game and had a bit of choppiness, set monitor to 60Hz and turned off VSync (Radeon 9500) and it runs sweet as, well....sugar. Or something sweet.
Anyway, first impressions:
The players seem to have "weight" to them, as if suddenyl they are affected by gravity more than PES4, well not more, just ina more realistic manner...hard to explain.
The passing is harder, and players first touches don`t seem too good all over the park, but that will just take some getting used to.
Dribbling is better (imo) and if you get up a head of steam the players really fly (well I was Henry at the time

), also battling is more scrappy and realistic although I think a few of the fouls that were given against me were harsh (simple shoulder to shoulder when running through on goal).
The shooting is far improved, and you seem to really be able to ping the ball, from anywhere and at any height, rather than some of the weak ass not-even-half-a-shot efforts I`ve seen in PES4.
the passing is good too, seeming to be able to kick a lot further and direct that PES4, in which any balls through seemed to float and allow the defenders to get under it.
I`ve also actually won scrappy battles in the middle of the park that would have been possible in PES4, little ricochets and animations that make it really sweet.
I think its all about the "weight", which seems to apply to the player and the ball, it makes everything seem more real - it`s been very well implemented.
On the downside, there was a few occasions when the players seemed to run in a direction of their own choosing, even though I use manual and Super Cancel to move off the Auto line straght towards to ball.
They don`t run off at a random angle, but they also don`t go exactly where you want, sometimes veering slightly - which is enough for the player your chasing to skip past you - especially with the new weight thing I`m on about.