@Gubar: With the limited experience I've got I do know that there has to be some common ground if that isn't there, it doesn't matter if you are face to face.
Try putting together a artyfarty conceptartist and an UberTech programmer in one room, they wouldn't understand each other.
The time zone difference at least the way I see it could be an advantage as well, you could have like 24 hour productiontime and you can agree with each other that you stay up a bit late or get up a bit early to have a bit of a chat.

I for instance live in the Netherlands, if I have to speak someone in America I can often reach them from 15:00 ( if they are eastcoast of course) for UK based companies it would matter even less.

I think it depends on the company and the artist if it works or not