I can no longer find the place where Branko asked about this, but here's a partial answer to his question why so many blogs have small fonts specified, against general best practices in web design/usability. Short version: Microsoft is to blame. (Via Opera Watch, via The Register.)
The other part of the answer is that the blog's designer may be testing his design work in a web browser that allows users to set a minimum font size and not actually realise that the "x-small" in the templates he is painstakingly adapting to his wishes is really too small. Ahem.
