I picked this book up thinking that it was a light, humorous romp poking fun at a bunch of princess tropes. (There's nothing wrong with that sort of thing, if you're in the mood for it, and I frequently am.) This is not that book. Well, this is sort of that book, if you took that book and added ten times the depth and maturity, and then sprinkled in a generous helping of solid story-telling.
The Princess Curse is a mix of many different fairy tales, so skillfully done that I didn't even notice the Beauty and the Beast one until someone else pointed it out-- and it's very obvious, I was just so engrossed in the story by that point that I didn't pay any attention to it. The author has several opportunities to go deep into Creepy Land with her child brides, and very pointedly does not do so, which I appreciate.
I'd give it 6 stars, but I've subtracted one for the lack of a sequel. You left yourself so many good hooks, Ms. Haskell. Please, I beg of you, write about one of them. Or all of them.