City Brights: Howard Rheingold : Twitter Literacy (I refuse to make up a Twittery name for it)
http://www.sfgate.com/cgi-bin/blogs/rheingold/detail?entry_id=39948

why twitter - one of the best articles to explain why

Twittermania is definitely sliding down the backlash slope of the hype cycle. It's not just the predictable wave of naysaying after the predictable waves of sliced-breadism and bandwagon-chasing. We're beginning to see some data. Nielsen, the same people who do TV ratings, recently noted that more than 60% of new Twitter users fail to return the following month.

When I recently participated in a live discussion onstage, we projected in real time the tweets that included a hashtag for the event, an act that blended the people in the audience together with the people on the panel in a much more interactive way than standard Q&A sessions at the end of the panel. After years as a public speaker and panelist, I found it fascinating and useful to have a window on what my previously silent audience was thinking while I was talking. You have to be sure enough about what you are saying onstage to keep from being distracted or thrown by the realtime feedback. Backchannel twitterers have been to virtually mob speakers they felt were wasting their attention.

Excellent post on social media literacy using Twitter as the key example. It is not about the tools, it is about an online culture. This article attempts to identify characteristics of this culture. For example; "Twitter is not a community, but it's an ecology in which communities can emerge...It is a platform for mass collaboration. To oversimplify, I think successful use of Twitter means knowing how to tune the network of people you follow, and how to feed the network of people who follow you."