This is a pleasant, nicely written new fairy tale, with likeable characters and a smoothly drawn environment. It's a fun read, for the most part. Unfortunately, as is often true with Shinn, the story is heavily wrapped in traditional stereotypes and gender roles. The boy is hyperactive and muscular; the girl is quiet and obedient. It's an approach that was substantially outdated long before the book was written in 2004.
Despite all that, Shinn is a good writer, the characters (under the stereotypes) are nice, and the story is well-balanced, so it's a fun story to read. It's disappointing, therefore, that Shinn undercuts it all with authorial legerdemain that, when revealed, wipes out most of the reader's goodwill. She's created a nice world, and there are apparently other stories in it. If you want a good young adult book, and can set aside the gender issues, it might be fun to explore those.