The game doesn't take place only in France. They said that the zed plague spread all over Europe, so I guess we're going to have several maps scattered around europe and several characters with differents European accents.
This is what I hope too!
English (British), French and German dialects.. maybe even Swedish!
Anyway, my biggest hope for this is that each voice becomes a module, which you can choose in your profile as a compliment to your player skin.
Like, I use Mr. Foster and his default is English, but I rather have a German dialect on him so I switch voice module.