Just to clarify, it is only 25% of this particular book. Sounded to me like the delivery charge was fairly independent of the cost of the book.
Maybe it has something to do with the book it's self (i.e. they charge $0.07 per image), but do they mention how this is calculated anywhere?
If I sell an ebook for $2, they take $0.60 in general, and then they decide that it costs $0.80 to deliver... that means they're taking 70% of the cost of the book. So if I'm successful and have to pay taxes, I may be making like $0.12 per book.
I don't remember every seeing this cost mentioned before in the few articles I've seen about selling Kindle books. I'd love to know how it's calculated.