Yeah - it's hard to say.
Serbia play a predictable European style game, but without the finer finishing touches of say, Germany or Holland. Against the flamboyant skill of Argentina, or Brazil, they don't stand a hope in hell.
They just don't have the players.
Germany and England do have the players, but it all depends on how well they play thier style of football - the no nonsense solid european approach, as opposed to the wilder, riskier, more emotional south american style.
Argentina and Brazil are obviously the strong favourites to win, but anything can happen.
Of course, I'm holding out for England, if they go (very likely), I'm hoping for Brazil to take it - I love thier passion for the game.