I disagree with some of this, in fact with a lot of it, though it does seem that when Evan describes the mechanics of those who have moved to digital reading, he is on the money!

While I see the logic behind this understanding – I posit a slightly more nuanced definition of what is happening: Ebooks aren’t cannibalizing print books — consumers with ebook reading devices are, as a rule, no longer buying print books. Subtle? Yes, but from a commercial publishing point of view this is a crucial difference between seeing a direct correlation between ebooks and print books and understanding what happens to a customer when they make the switch to reading devices.

via Ebooks Don’t Cannibalize Print, People Do « Black Plastic Glasses.