Page last updated at 03:21 GMT, Sunday, 15 March 2009 Status updates on sites such as Facebook, Yammer, Twitter and Friendfeed are a new form of communication, the South by SouthWest Festival has heard. "We are all in the process of creating e-mail 2.0," David Sacks, founder of business social network Yammer said. Tens of millions of people are using social networks to stay in touch. The growth in