Internet media things as if you were browsing the internet using your PS3?
As I never do that so I could keep them off.
www.winningelevenblog.com
www.pesgaming.com
IGN mentioned the slow down aswel.
So it is definately there.
Apparantly if you install bits to your HD though it makes it better so I will do that aswel.
I read on one of those 2 sites aswel that when Konami compared the PS3 version and the X360 version running side by side, they could notice more slowdown in the PS3 version but they dont know why.
Seabass has said aswel that there wont be any downloadable content for it either but if it is really as bad as some people say surely they will have to see if they can make a patch to fix it.
EDIT: Oh and I've played the full version of Fifa. Its better than the demo but its still awful in my opinion. Still too slow and un-responsive and not at all fluid.
PES6 on the PS2 is better imo.