Look closely at the pricing on Amazon for this book. The hardcover is $7.99 and the Kindle edition is $9.99!
Electronic books cost less to produce and distribute than physical books, there are no costs for inventory or returns, you can't lend them and you can't sell them when you are done. So they should always be priced lower than the physical book.
This is not Amazon's fault. The initial Kindle pricing model was that Amazon would set the prices. The publishers disliked that so much that they threatened to withdraw their books from Amazon with this very publisher, HarperCollins, leading the charge.
You might wonder what HarperCollins' agenda is. I can only surmise that they hope that they can sabotage the move to electronic books and maintain their current business model. Of course they would think that, because resisting digitalisation has worked so well for the entertainment industry!
When Amazon write "this price was set by the publisher" I don't know how they can resist adding "who are complete idiots and deserve to go the way of the dinosaurs."
Update: 6 October. I wrote this before I saw this article on the same subject in the New York Times.
The article discusses two specific examples and the publishers are quoted as saying "...those two books were the first they knew of that cost more as e-books than in hardcover on Amazon." Not only are they idiots, but they are either liars or completely and utterly clueless. I've seen dozens of examples on Amazon including some where the electronic book is more expensive than the paperback!
Hopefully enough pressure is building on publishers to stop this nonsense. By the way, I think the New York Times is much less imaginative with its headlines than I am!