When singer Whitney Houston passed in February 2012 the news broke on Twitter nearly 30 minutes before hitting mainstream media. The same goes for the 7.6 earthquake in the Philippines last year, Patrick Swayze's death in 2009, the unveiling of Google's Nexus One, and the Hudson River plane crash in New York City. Think what you will of Twitter, but it's become a fact of life: the micro-blogging site is now a source of breaking news.