From Eric Alterman's New Yorker piece on the sad fate of American newspapers:

Despite the many failures at newspapers, the vast majority of reporters and editors have devoted years, even decades, to understanding the subjects of their stories. It is hard to name any bloggers who can match the professional expertise, and the reporting, of, for example, the Post ’s Barton Gellman and Dana Priest, or the Times’ Dexter Filkins and Alissa Rubin.

Well, gee. Let me try this.

Economics:

• Brad DeLong
• Greg Mankiw

Law and Civil liberties:

• Glenn Greenwald
• Jack Balkin, et al.

Physics:

• Chad Orzel
• Jacques Distler

Middle East Politics:

• Juan Cole
• Marc Lynch

Baseball (a nonpartisan list!):

• Curt Schilling
• Phil Hughes

And that's enough to make the point, though I could go on quite a bit longer, in each of these fields and plenty of others (biology, French politics, you name it). On almost any topic, there's a genuine, experienced, even formally credentialed expert blogging about it who has spent large chunks of their life wholly devoted to the field, and who has more, and more interesting, things to say about it than anyone who spent equal chunks of their life hanging around a newsroom.

I'm not trying to say here that the whole journalistic enterprise was without value, but its denizens and partisans, like Alterman, won't help preserve it by maintaining their willful blindness to one of the major reasons that bloggers on the internet are eating their lunch.