Skirmish is set to be Multiplayer-only. Games will be played using TCP/IP. When the game starts up, it will find your IP address. You can tell this IP address to your friends, and they can join your game by typing it in. Your IP address will also be posted on www.skelman.com, so others can see your game to join. You'll have the option to disable this.. Other Skirmish players can come to www.skelman.com/skirmish/ and see what games are available to join.
If you have any questions/comments, let me know via email.