Here are two interesting excerpts:

The radical change was de-coupling groups in space and time. To get a conversation going around a conference table or campfire, you need to gather everyone in the same place at the same moment. By undoing those restrictions, the interent has ushered in a host of new social patterns, from the mailing list to the chat room to the weblog.

We have historically overestimated the value of network access to computers, and underestimated the value of network access to other people, so we have spent much more time on the technical rather than social problems of software used by groups.