No, this is not the same old beaten horse.
Revere at Effect Measure, one/some of the best public health writers on the web, has written a splendid piece on the difference between the two types of blogging in response to the denial of his registration at the Knight Science Journalism Tracker. Revere has intended to comment on their coverage of the Brownlee and Lenzer cover article on swine flu at The Atlantic.
I was going to pick out some excerpts but the whole post is so clearly written and important in its entire context that I refer you to read it in its entirety.
I don't believe that I have ever read a more insightful treatment of the "pseudonym" issue regarding those blogging about science and medicine.