Basic idea: boy turns to wolf every time it gets too cold.
Imagine if Twilight's Jacob character was an emo teen who turned into a regular old wolf (instead of a werewolf) and eventually would get stuck forever as a forest-dwelling howler and you've got Sam, one of two mains characters in Shiver. Grace has watched a certain yellow-eyed wolf roam outside her home ever since she was bitten by a pack of wolves as a child. The affinity she feels for this certain wolf becomes realized when she discovers that he is, in fact, a shape-shifting boy named Sam, and the two develop a plodding smooch-filled teen relationship that largely involves him waiting in Grace's car while she goes to high school. As is my major complaint with most teen books, the parents are conspicuously infantile or absent. In this case, the parents are artistic dingbats who are never home and when they are home tend to do weird things like paint in the nude and forget to make dinner, which makes it very easy for Sam and Grace to develop a lets-play-house relationship. Maybe there really are parents like this. I don't know. Even being raised by a single mom as a teen I wasn't allowed to have my bedroom door closed with my boyfriend over, so maybe it's just outside of my reality.
Anyway, the language is lovely and the first half of the book is especially well-written. It invokes the feel of the stark northern mid-west (think Leif Enger's Peace Like A River>. While not fully developed, the characters are thoughtful and interesting and the premise of the wolf transition is a new take on the ever-popular werewolf theme. If you're on Team Jacob and need some good werewolf filler, go ahead and pick it up!