Yesterday afternoon I dove into this book (I'm slowly making my way through my TBR pile...) It was intense, but I expected that. What I didn't expect was the lesson I learned afterward as I scrolled through the reviews on Amazon.com. A huge number of readers were FURIOUS over the bait 'n switch the author pulled, promising her sister's story and spending 98% of the book telling her own instead. I didn't disagree with their assessment, but I was surprised by how angry they were.
They weren't disappointed in her story--it was almost as grim as her sister's. But they hated being duped into buying the book based on something different than what it actually was. The general sentiment was that either your story stands on it's own literary merit or it shouldn't be published. But you shouldn't lie to readers.
It made me think of a few other books I've felt disappointed by for similar reasons, and made me take a bit more seriously the relationship between my titles and the stories I tell.
What do you think? How much leeway do you give the relationship between a book's cover and it's content?