Anyone who really wants to understand the business dynamic involved in selling pbook vs. ebooks needs to go to Black Plastic Glasses and read the "best of" posts at
http://www.blackplasticglasses.com/2...hnittman-blog/
If you don't understand what drives the marketing of pbooks, you won't understand why the marketing of ebooks is a problem for publishers and resellers. It's not about the "costs" of making an ebook as compared to making a pbook. It's mainly about the cash flow.