Just a few years ago, when user-driven media was in its infancy, even the strongest supporters worried about its capacity to inform the public, a role the mainstream media had claimed for at least a century. A well-known advocate for expanding the role of citizens in journalism, Dan Gillmor, wondered and worried in 2004 what would happen to the traditional business model for journalism when we reached the tipping point where the audience for traditional media shrank, and user-driven media surpassed it:

“Who will do big investigative projects, backed by deep pockets and the ability to pay expensive lawyers when powerful interests try to punish those who exposed them, if the business model collapses? Who would have exposed the Watergate crimes in the absence of powerful publishers, especially The Washington Post’s Katherine Graham, who had the financial and moral fortitude to stand up to Richard Nixon and his henchmen.At a more prosaic level, who will serve, for better or worse, as a principal voice of a community or region? Flawed as we may be in the business of journalism, anarchy in news is not my idea of a solution.”

For now, the percentage of Americans who rely exclusively on news from user-driven sites is just a fraction of what it is for mainstream news sites.And in this increasingly fragmented era, many who visit Digg, Del.icio.us, and Reddit may also be reading the online versions of The New York Times and The Wall Street Journal.But whether or not we see further divergence between user-driven sites and mainstream media over the next few years will surely remain a key question for researchers, journalists and of course, citizens.