After looking at and trying other IM server based on Jabber/XMPP we decided to use the iChat server built into Mac OS X Leopard server.  It was one of the few that supported native video and audio chats.   The video and audio are just initiated by the server but are not routed through it.  This minimizes server bandwidth usage.   It also supported chat rooms that could be created by any authenticated user.  It is easily managed through Open Directory and has SSL connection capabilities.  It can also be set up to use Active Directory or LDAP.

I just had the opportunity to put video conferencing to a real trial by fire in an unexpected setting - a hospital waiting room. The other challenge was making the link using only a cellular broadband card — no ethernet, no wifi.