When I read Shiver a while back, I wasn't thrilled with the story or the characters, but I still put the book down feeling like Stiefvater had some real writing skills. So I decided to give Lament a chance, because fairies. I am glad that I did, but...While I was reading Lament, I really liked it. Didn't much care for the main character, or for the romance with Luke. (I don't care how cute he is, grow a sense of self-preservation!) But now, having forgotten to review the book for almost a week... I don't remember much. Didn't even remember the main character's name. It seems that it failed to leave a real impression on me. I do remember that there were some completely unexplained plot threads. (Naturally, there is a sequel.) But I'm more irritated than intrigued by the delayed explanations (if any are ever given).
I did like the way the fairies were handled. Dangerous, capricious, and entirely not human. But that isn't really innovative anymore. Using the concept of a gallowglass was interesting, but it isn't entirely explained in the book. (The main character is told to google it, and she does, but she never tells us what she read. I suppose the reader is meant to google it, too, so I did. In medieval Ireland, gallowglasses were elite infantry of Scottish descent, which is at least as cool as a fairy assassin.)
I guess the final verdict here is that Lament is a pretty good YA paranormal romance, but ultimately forgettable.