Farkel,
I have to agree with you about prefering sans serif fonts for reading online. I would bet the reason has something to do with the fact that most of the studies for the web and online reading make the claim that your reading speed will improve when a site uses sans serif fonts for their text. It's only in the world of print that serif fonts begin to improve the speed of the reader.
Dave
"Vision is the art of seeing things invisible"
Swift