I wanted to comment further on a point highlighted by Ann Althouse:
[J]ust counting the numbers of bloggers is not very accurate. For example, Chicago has a high blogger count because it runs a group blog with a long list of faculty names. I'd like to see a weighted count — if you're going to get into counting — that reflects the actual amount of blogging that is going on. But then if you did that, you'd probably want to count the blogging that is specifically about law, as opposed to, say, "American Idol."
Indeed, the school-by-school counts of law professor bloggers are:
14 University of Chicago
7 University of California at Los Angeles
7 University of San Diego
5 George Washington
5 George Mason
4 Ohio State
4 University of California, Davis
4 University of Cincinnati
The problem with this list is obvious: Can Chicago really be the leading blogging law school without a single major blogger on its full-time faculty? Dick Posner, who is a part-time senior lecturer there, runs an excellent and reasonably popular blog with Gary Becker that nonetheless gets in a month roughly as many visitors as Glenn Reynolds gets in a few peak hours in a single day.
Former dean and former provost Geoff Stone blogs at the extremely popular HuffingtonPost, but he contributed only one post to Huffington in the month of February.
Most of Chicago's bloggers post at the U. of Chicago Faculty Blog. Though also of high quality, it had barely more than a dozen posts during the entire month of February. It will probably evolve into a successful blog, but with 3-4 posts a week on average, there is not yet enough content to generate regular readers.
From skimming the list of the most popular blogs at The Truth Laid Bear on Tuesday night, it appears that the most popular blog run mostly or completely by full-time professors in any field is Instapundit (8th in traffic, 2d in links), followed perhaps by the Volokh Conspiracy (55th in traffic, 11th in links). Although the TruthLaidBear.com website doesn't track all blogs, it appears that we are a distant second to Glenn among all academic blogs, whether measured by links or by traffic, It is entirely possible that I've missed an academic blog in another field between Glenn's blog and Eugene's group blog.
One of the problems in doing empirical research is the quantitative fallacy: the belief that what is easiest to count substantively counts the most. Although Chicago may develop into a significant blogging law school, it does not yet reach the influence in the blogosphere of UCLA, Tennessee, San Diego, GW, George Mason, or Wisconsin, among others.