I haven't got the game yet either, but I won't let that stop me...

In MTW games were saved to a single file, and you could copy them around, so you could transfer them to another machine. Presumably RTW is the same.

However, if you wanted an e-mail campaign, surely each participant would have to take it in turns to play as the same faction, each player progressing that faction's campaign a little bit more. I can't see how you would be able to have an e-mail campaign where everyone is playing a different faction.

So this would be great if you are into non competitive sports and love cooperative play, but not so good if you want to thrash your friends.