When you enter a lobby you can change 'multi platform' into yes or no.
I've played one game today against a friend of mine who owns the PC version (I have the PS2 version) and it played like a dream. We live in the same city and both have high end ADSL connections. Absolutely no lag, none, nothing!
Also no half time connections and stuff, just plain good football.
We met in English/French, common friendly lobby. It's there in the middle.