To start, there are a lot of elements I really liked about this book. For starters, the writing was very well done: descriptive and artful. It was also a very different concept for a YA fantasy book from what I've read, from start to finish. Luce, our protagonist, is sent to reform school after her bystander-involvement in the fiery death of a would-have-been boyfriend. It's there that she meets a few new friends, a couple of mean girls, and, of course, a couple of boys that make her heart flutter (in very different ways.) Without giving too much away, I also really admired the concept of the fantasy element in this story. It was a big undertaking, and for me it made the story.
Unfortunately, although it's hinted, this element doesn't really come to light until the last 40-50 pages. It piques my interest about the sequel, but I never attached to the protagonist. I liked all of the other characters better than her. Luce's reaction to things great and small usually went against my own instinctive reactions. Because it's written in third person, the author can get away with using more omniscient descriptions in Luce's reactions, but it became distracting and almost aggrevating for me. At one point, something really horrible has just happened and Luce is in pieces, and then she's thinking about scrubbing her fingernails.
Daniel - love interest #1 - has some epic mood swings, and gave me emotional whiplash. His reasonings are well explained towards the end, but if I was Luce I would've told him where to go and how to get there after the first interaction. I like a little volatility, but it was a little too much of a roller coaster for me, especially because so much is a mystery or just hinted out throughout most of the book. Maybe it would've read better for me if it was done in 1st person, because although it's in 3rd, it's a very limited POV.
All in all, I would still give it 3 1/2 stars because it is well written and the fantasy element Lauren Kate tackles is EPIC, to say the least. I also really like a lot of her secondary characters. I just didn't hit it off with Luce. I know I'm in the minority here, obviously, because it's a New York Times Bestseller and has several successful sequels behind it. I can see why the teen market would eat it up, it just a little confusing for me.