This is a hard book for me to rate.
On the one hand, it was a page-turner for me (I usually stick to nonfiction), and I felt it was well-written...the turns of phrase and the simplicity of the telling. So I enjoyed that. I liked the premise an awful lot.
On the other hand, I'm not sure how much I...liked it. I spent a majority of the time being annoyed with their attitude and having to remind myself that they're supposed to be teenagers. Still it was like, "you've lost everything you thought was important, why do you keep treating each other poorly?!"
Unlike a lot of reviewers here, the end was about the only part I liked, even though it's a little too pat for my liking.
I find myself thinking about it a lot, though... maybe I'll have something more to say about it later.