Social networking for museum professionals

As one who has been involved with networking in the museum sector for many years, I know how difficult it can be to create cohesion among participants who may never have met each other face to face. The people behind Museum3 seem to have succeeded in doing this much better than any other social networking site I have been a member of. I think that this is tied to a combination of personal involvement by the organizers (such as the inclusive tone in which they greet new members, or their following up on interesting discussions), the well functioning NING service and interconnectivity with other blogs and networks.
I appreciate having networks like this for keeping in contact with colleagues. My salutations to Lynda Kelly and Angelina Russo for all the work they have put into Museum3!