I've been involved in this group for a month or so and the discussion is lively and very informative.
Participants are independent school teachers and administrators from all disciplines.
It is decidedly not just computer or technology teachers. Discussions have ranged from curriculum matters in all disciplines to the role of single gender schools. All you need to access this group is electronic mail capability. University School uses an e-mail exploder which was created for us during our space shuttle missions for communication with other schools. Hence you can send messages to hundreds by sending only one message.