I didn't even notice the ad until reading through the HN comments. My eyes went directly to the red copy since it was centered in the page (and the ad, which apparently is there, is white and to the right).
I also thought it was related to the primary subject... and the real image, I thought was an error message from the advert company for clickabuse or something..
So when the author brings up usability and UI issues... should probably recitify those on his own site, before reaching out to others.