Someone on the Barnes & Noble forums pointed out that the New York Times bestseller lists now include ebooks:
As one commenter pointed out, including ebooks on the list gives them credibility. It took a while for them to gain acceptance, but now that they are, their popularity seems to be snowballing.
It was also pointed out that many of the ebooks on the list are priced over $9.99, which is supposed to be the magic maximum price that customers will pay for ebooks. Guess not!