internet - Virtual communities: what makes them run?

Internet has wiped away time and place as defining elements, but what is coming in their place? When you look at Craigslist.org (one of the speakers this morning) locality still seems to be important. Susan Mernit defines also e-bay as a 'trading community' . People want to have a real world connection. "The network is the database" says Mark Pincus of the Tribe Networks. "People want to have a voice". A revolution of the ants.
Markos Moulitsas of Daily Kos, of a political blog: we were nobodies when we started. We built a community online, without any credentials and could build up this community.