To be sure, some important differences exist between the current generation of public intellectuals and the Partisan Review generation extolled by so many. In the current era, many more public intellectuals possess social-science rather than humanities backgrounds...Very true, very simple. And if it's an unfortunate truth for humanities souls, it's more unfortunate that we are so often loath to admit it.
That fact in particular might explain the strong belief in literary circles that the public intellectual is dead or dying... What made the New York Intellectuals stand out, however, was that they started in literary criticism and migrated to social analyses. When social scientists like Tyler Cowen or Richard Posner return the favor, they are viewed as either arrivistes or methodological imperialists.
Well, I think 'quality control' is highly optimistic, but the jaggedness of the integration of blogging into intellectual life has certainly opened up some new opportunities (Nate Silver of fivethirtyeight.com is probably the latest example) for commentators with comparable skills but non-traditional backgrounds to find a voice in a debate or a discourse. That's something worth cheering.
For academics aspiring to be public intellectuals, blogs allow networks to develop that cross the disciplinary and hierarchical strictures of academe. Provided one can write jargon-free prose, a blog can attract readers from all walks of life — including, most importantly, people beyond the ivory tower. (The distribution of traffic and links in the blogosphere is highly skewed, and academics and magazine writers make up a fair number of the most popular bloggers.) Indeed, because of the informal and accessible nature of the blog format, citizens will tend to view academic bloggers that they encounter online as more accessible than would be the case in a face-to-face interaction, increasing the likelihood of a fruitful exchange of views about culture, criticism, and politics with individuals whom academics might not otherwise meet. Furthermore, as a longtime blogger, I can attest that such interactions permit one to play with ideas in a way that is ill suited for more-academic publishing venues. A blog functions like an intellectual fishing net, catching and preserving the embryonic ideas that merit further time and effort.
Perhaps the most-useful function of bloggers, however, is when they engage in the quality control of other public intellectuals. Posner believes that public intellectuals are in decline because there is no market discipline for poor quality. Even if public intellectuals royally screw up, he argues, the mass public is sufficiently uninterested and disengaged for it not to matter. Bloggers are changing that dynamic, however. If Michael Ignatieff, Paul Krugman, or William Kristol pen substandard essays, blogs have and will provide a wide spectrum of critical feedback.