In “internet time” blogging has been around for almost an eternity. Now, with the possible exception of the odd intransigent high court judge, blogging has achieved household name status since catching the public's imagination nearly a decade ago.

The medical “blogosphere” is an especially crowded firmament. The opportunity to access raw, unfiltered material, to post instant comments, and to share information with a (often niche) community has become an addictive pastime for many doctors. The field has developed to the extent that devotees rely on their favourite blogs as their first port of call for topical opinion and debate. Taken as a group, the medical bloggers—the popular ones, at least—are overwhelmingly younger men, and many have a typically masculine geeky humour.

But the field is far from just a playground for the young. For example, David Colquhoun, professor of pharmacology at University College London, is 71 and now a celebrated blogger in his field. Professor Colquhoun thinks that a blog's power lies in its independence. Unlike newspapers, blogs don't feel bound to present a balanced picture, he says, “which, only too often, means giving equal space to people who believe the earth is flat and those that don't.

“On a blog I can just give my view. It's obviously that—and people can take it or leave it. Also, bloggers often seem …