Word has come from Polygamia.pl that the upcoming release, Mercenaries 2, will not allow regional multiplayer across Xbox Live.  This means that PAL territories will not be able to play with NTSC territories.

Stranger still is the idea that if you own the Spanish version of Mercenaries 2, you will not be able to play with someone that might have the German or Portuguese version of the game. 

I know that Army of Two did not allow region multiplayer, so I could not play with my friends in Europe, primarily for smoothing out the jumps in the lag between countries, but to think that next-door countries like Spain and France would not be able to play against each other because of a language block seems a bit ridiculous.  Hopefully Electronic Arts will clarify this with a press release, but considering they published Army of Two, I would put good faith in this being true.