Amazon reported today that it is now selling more ebooks than printed hardcover. Over the last three months, ebooks are outselling hardback by 43% and over the last month (since the big price drop on the Kindle), ebooks are are selling 80% more than hardbacks. These figures do not include free ebooks.
Amazon notes that while the American Association of Publishers is reporting that ebook sales are up 207% over the first five months of the year, sales of it's own Kindle format ebooks are up over 300%.