Mike Shatzkin has a smart analysis on what is lost, perhaps even for J.K. Rowling, when authors or publishers disintermediate to the extent that, far beyond notions such as “direct to Kindle,” they sell their books direct to the public:

Directly from Shatzkin: “I’m quite sure that fewer Harry Potter ebooks will be sold by the Pottermore strategy than if they were just made available through the standing ebook retail network. The margins might be higher with no retailer to pay, assuming that advantage isn’t completely swallowed up by their own costs of infrastructure (and it probably won’t be.) But not everybody who buys a Harry Potter book from Amazon or B&N (or a Nora Roberts book or a Janet Evanovich book or a James Patterson book) is a devoted fan. Some of them are just choosing their next read and if Roberts or Evanovich or Patterson wasn’t shown to them, they would have bought something else on offer. “