Attack = Attackers now have a better AI, they will now strafe or hold back with their runs to counter act the off-side trap.
Dribbling = Is now more realistic, when you change direction you stop dribbling and have to start again. Insted of the continuously dribbling you have in Fifa12
Ref = The ref will now book and send off goalies (at last lol), also the AI engine has been rebuilt.(so EA said but I couldn't see this).
Passing = You can no longer do the over powered 50yd ball straight to a team mates feet (unless you are Ronaldo or Messi). You will have no chance of doing it with sides such as Southampton etc.
First touch = Is now more realistic, how hard you pass and the spin and the players stats you're passing to all are taken into account. So more often then not players will need more then one touch to control the ball.
Precision play = All I can say on this is it is even more over powered then before
Free kicks
Taking = You can now customize your free kicks more (was told you can do it in game aswell, but it wasn't built in yet)
Defending = You can now change the amount of ppl in a wall their positions etc (up to 5 in a wall if i remember rightly)
The wall will now be able to jump to block the ball more then just the once unlike in previous FIFA's.(plus the AI has been tweaked)