An article pointed out on the Amazon boards: E-book sales nearly double in a year, trounce hardcovers in August. "Hardcovers tanked in August, down nearly 25 per cent year-over-year. There must have been a lot of Kindles at the beach: e-book sales for the same month were up 172 percent."
This is, of course, based on an Association of American Publishers report, which would not include small presses and indie books. But I like to think a rising tide lifts all boats:-).