Nope, I don't think that we need it. From all forums that I used, shoutbox is something that I never used. Maybe it can work in smaller forums, but not in place like Bitcointalk where there isn't much common between different members.
And I'm just going to quote post from that old topic. Not that I completely agree with it, but it's just epic:
Shoutboxes are about as entertaining as contracting AIDS and dying a slow, painful death.
NO, THANK YOU!
In all seriousness, I think this will just take away from the actual discussion on the forum, and probably actually result in hindering it.
I don't think so. Nobody is going to change posting for signature campaigns to chatting for free.