Well having read some very mixed reviews here's where I am with it after playing maybe 9 or 10 games...
I enjoyed it immensely, I thought it was easily enough of an improvement on 09 to warrant paying £45 for. The movement impressed me massively, when you have a player take posession of the ball his team mates seem to be working to find space which is great.
One thing that I haven't seen mentioned yet is the crossing. I think this has improved hugely since 09, it's an absolute joy to whip in crosses now, especially with new animations for headers too, I played a match with Bayern against Marseille and having led for most of the match 1-0, coming into the final 5 minutes Marseille pushed forward and Hamit Altintop stole the ball, fed Ribery darting down the right flank who beat his man and whipped in a cross towards the far post about 12 yards out, Klose was tussling with Hilton in the centre and just expertley rose above him and nodded the ball into the opposite corner. However simple that sounded you can't believe how beautiful it was to see.
Long range shots are something that irritated me in 09, they seemed very floaty and light, now they are a lot more realistic, providing you have the right player. I tried a long ranger effort with John Terry when I was playing as Chelsea, not for any particular reason, he just strode out of defence and as the opposition defence backed off I let fly from 35 yards, it was utterly embarrassing and very realistic. Then tried a 30 yarder with Mark Van Bommel which really tested the keeper, you get the impression that with a bit of time and practice, scoring one of these will be very special.
I read somewhere that this demo is three builds older than the finished version, I love the game already so three builds later, I really cannot wait for the full and final game to be released.