FFXI's Friend List was also handled differently though - it was part of the external Playonline Viewer and not the game client itself, so it could connect remotely to all servers (and even cross game, well, the few games that actually used POL that is.

So unless SE similarly moved the Friend List into the launcher client (which would probably just be too much trouble than it's worth), I don't see it happening sadly. It would be great if SE could do this though - I've met lots of friendly people through Duty Finder which I would have loved to have connected with but couldn't due to being on other servers.