I just recently found out this very blog of mine was found and ranked by the Chemical blogspace as number 96 (out of about 250, before you ask). I still don’t know how do they do the math but it seems it has to do with the number of clicks a blog gets over a certain period of time and relating that somehow to the number of new posts over that same period.
J. Barroso (Wed,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: