I couldn't help but notice that Andrew Sullivan wasn't blogging this past week. I noticed it in the same way one might notice a large sinkhole in front of the house—something big and important was missing, and in its place was a void. Having been neither a particular fan nor a detractor of Sullivan's long-ago tenure as editor of The New Republic, I'm a little surprised by how deeply I admire and rely upon his blog, the success of which seems at once a harbinger of a bright future for journalism and a sign of just how tenuous that future could be.

Sullivan has years of experience as a print journalist, and no doubt has benefited from his associations with other talented practitioners of the traditional craft. But his Daily Dish blog is a personal showcase that could only exist on the Web. In it, he gives his passions and prejudices a long leash while at the same time using his powerful intellect and critical faculties to raise questions, examine issues, wage feuds, advance crusades, and rebut fallacies. It's also a platform that affords him great influence, which, in the meritocratic ways of the Web, he has earned single-handedly—without the high visibility of an opinion column in The New York Times or The Washington Post, both of which provide the kind of institutional backing that can (and not infrequently does) transform even mediocre thinkers into market leaders.

Sullivan was an indispensable source of insight and criticism throughout the long presidential campaign. But as Hendrik Hertzberg pointed out in his own New Yorker blog, Sullivan's recent coverage—and that journalism term takes on new meaning here—of the uprising in Iran was nothing short of extraordinary. "Revolutionary" might be a better word.

In the first weekend after the Iranian election, when the street protests seemed to bubble up from underground, Sullivan's blog was beyond compare, extracting original reporting from professional and nonprofessional sources inside Iran; filtering the best of the BBC, The New York Times, and other quality news organizations; and providing a buffet of nuanced, sophisticated, and expert commentary on what was—or might have been—taking place. Sullivan's own passionate response to the events provided gripping color commentary, but more than anything, it was his curatorial intelligence that made the site crackle with energy, insight, and urgency.

With the help of a couple of assistants, Sullivan produced a journalistic tour de force that was more comprehensive, informative, provocative, and addictively compelling than anything produced by news organizations with hundreds of professional journalists on staff and coteries of experts on speed dial. His Iran coverage was the blogosphere's moonshot, a feat of grit and daring heralding a new era in cyberspace. It was a preview of the future of journalism—and it worked. Or seemed to.

Before we celebrate the death of old media and birth of the new, however, it's perhaps worth noting that there aren't a great many Andrew Sullivans. A venerable institution like the Times can take a pretty decent journalist and—using its vast institutional resources, its culture and history, its quality control, its capacity for expert editing—elevate the caliber of that journalist's work by several degrees. That's what a great institution does—make good people better while mitigating the damage inflicted by mediocrities (and the occasional fraud). 

Whether the Times is as great as it once was is not really the question (and, it appears, not much in dispute, either). The question is whether in his talent and commitment, and in the quality of his discernment, Sullivan is a replicable product, one ideally suited to the demands of a medium that, so far, displays no tolerance for the expansive and expensive quality layers of an institution like the Times. To assume that a new world of Andrew Sullivans can supplant the old world of The New York Times is to assume, among other things, that an abundance of individual excellence can take the place of collective, institutional excellence. If Andrew Sullivan is the model of low-cost, high-quality distributed journalism, then how many brilliantly talented, passionately committed bloggers does a healthy republic require?