It turns out that Dogs of War is expanding at a good pace. Now: multiplayer (including coop) sessions of Scourge of War Waterloo.
Please check out this forum thread for details:
By the way, the Dogs of War honcho Asid has introduced me to the Kriegspiel mod and let me tell you it is a game changer! In addition to new features, this mod packs a lot of content. Don't miss it!
Dogs of War play in hardcore mode, with no even map updates. But the sessions appear to be quite fun and develop in an inviting atmosphere.