Last night, many of us learned about Osama Bin Laden's death on Twitter . And in fact, the first credible report from Keith Urbahn, former Secretary of Defense Donald Rumsfeld's chief of staff, was also on Twitter. And while the White House kept pushing off the official announcement for an hour to inform different parties, the news was already being analyzed and spread on Twitter. So did Twitter supplant mainstream media as the best source of news about Bin Laden's death? Yes and no. Yes, many people first heard about the news on Twitter, but more often than not the original source of that news could be traced back to mainstream media. Bin Laden's death was confirmed by mainstream media (CNN, NYT, etc). Even Keith Urbahn notes that his source was not someone in the military or government, but a "connected TV news producer:"