It's not about what they add in a seacom. As long as a player is linked to the playonline thing, then it will display your current mission for - Nation, Zilart, Promathia, ToAU, Assault, Altana, Campaign, C.Prophecy, M.KupoD'etat, S.Ascension.
Edit: It seems like you might have only read "I don't think the player search is used often enough for missions." and thought I was talking about the in game /sea all, but I was talking about ffxiah.com's Player Search.
XI Wiki


