Interesting topic, but 40% seems like a high number of "buyers" with JS turned off. I wonder if they counted all web hits as "people who buy" and 39% of their hits came from bots.
There's another bit that I didn't include in the blog post because it was irrelevant to the point... which was that the people running without JavaScript had a high degree of (there's probably a more diplomatic word but what the heck) stupidity. Stuff like adding a "special instruction" to "make sure the book is signed" when the book description says this is a signed copy (and it's priced accordingly).
--Esther