I've been a fan of GalCiv since the OS/2 days. But barely played GalCiv III because multiplayer is such a chore with serial turns.
From what I've found on the forums/Steam reviews the game still doesn't support simultaneous multiplayer. These days I rarely play solo games, and my gaming group will pass on anything not simultaneous turns.
Any plans to add this to GalCiv IV? It is a go/no-go requirement for me.