According to this
LA Times article, Amazon has 76% of the ebook market, and the Kindle ap for the iPad is helping Amazon hang on to its market share, even with the huge growth in iPad sales. It says, "one in five people who buy digital books from the Kindle store don't own a Kindle device."
http://latimesblogs.latimes.com/ente...et-survey.html
Analysts also predict that by 2015, Amazon will only have 51% of the ebook market, and Apple will have 16%.
It's an interesting article.
L.J.