Citi Bank analyst Mark Mahaney maps out the growth of Amazon's Kindle device and ebook sales, predicting that ebook sales will outpace device sales in 2012 (3.7 billion from ebooks and $2.4 billion from the device). I note that he uses the term sales rather than profit or revenue.
http://techcrunch.com/2011/06/07/kin...-sales-amazon/