Have you ever read ebooks on a palm? It was pretty obvious to me that that was the future. It needed someone to take the idea seriously for it to become mass market. Amazon did.
Yes, I have read ebooks on a palm. And on a Psion 5 before that. (I started reading ebooks around 1996-97 and have been banging on about them ever since.)
Yes, O'Reilly. Yes also Baen (via Webscription.net). But there wouldn't be a mass ebook market at this point if the big publishing conglomerates -- who produce 80% of the books sold -- weren't on board with ebook publishing.
Amazon sold over 4 million Kindles in December alone, and now sells more ebooks than paperback and hardcover combined.
With one or two exceptions, every serious reader I know has a Kindle, an iPad, or both.