Interview extracts over on civfanatics.com
Last quote is of greatest relevance to these denizens.
On multiplayer:
What multiplayer options will be available?
We're going to have the basics out of the gate. About a month after release, we're going to add Pitboss. Pitboss will be accompanied by two extraneous modes that we weren't originally planning, but the fans keep asking for: play-by-mail and hot-seat.