Marin, CA Teacher Librarian Tom Kaun recommended a panel discussion on "Social Media as a Force for Good" with Twitter and LinkedIn founders and UK author/activist Stephen Fry. It was well worth the time (1.5 hours).
Stephen Fry said he got the most joy from Twitter about a year or so ago when he decided to use Twitter as "verbal post cards" for a trip to Africa to do a story on Rhinos. He suddenly got thousands of followers and started to realize the power and potential of Twitter. He also pointed out that humans are emotional creatures and need to communicate. Writing -- even on Twitter -- is a literary form. Twitter is an instrument of free speech.
Biz Stone (CEO/Founder, Twitter) said early on he saw how Twitter was used for "Tweet-ups" (like "meet-ups") to organize events or meetings. People in a conference session would tweet that a different session was more interesting, and lots of people like a flock of birds would leave the first session to go to the better session. Similar use of "Tweet-ups" for raising money for a charity, to do good. Biz said Twitter was created to do good.
Biz also said Twitter was created with mobile devices in mind, and mobile devices are growing way faster than desktop computers. Re: Twitter as news media -- it is good for breaking news, but journalists are better for putting news in context.
LinkedIn's Reed Hoffman, in commenting about social media trends, said "you haven't seen anything yet." "Web 2.0 is power to the people, a '60's expression." Social networking sites are platforms upon which other sites are built ("platforms" rather than "features" on a site.)