How is Twitter Dramatically Altering the Journalistic Landscape?

Protests surrounding elections in Moldova and, more recently, Iran have been singled out for their use of social networking tools, particularly twitter. Many have said that cell phones and text messaging played a crucial role in Ukraine's Orange Revolution in 2004/2005. But are these claims justified? And how is twitter changing the role that journalists play in covering international events such as the street protests in Iran? Can the new technology fill the void? John MacArthur of Harper's, media technologist Deanna Zandt, independent filmmaker and educator Simin Farkondeh, and Robert Huesca, a professor of communications at Trinity University, on the twitter revolutions and the future of journalism.