I would have to disagree that The Book Thief is about books' inspirational powers. I would have to say it is far, far more about the beauty, horror, and tenacity of humanity.
Just recently finished The Book Thief. Not the genre I usually read, but I absolutely loved it. To me, the selling point was that it was written in Death's point of view. It was also incredibly cool to see the way he was portrayed. I'd recommend it to anybody.