What @d_r said really, they had absolutely no right to go into your personal digital library and delete a book you bought in all good faith. I think cory is correct when he says it’s the same thing as breaking into your home to take a book out of your bookcase because the retailer shouldn’t have sold it.
I think if amazon believe they can get away with it they’ll do it again, as i’m sure they thought they could get away with it at the time but it created a lot of negative publicity for them.