Many bloggers I respect love this prequel to The Mortal Instruments trilogy. But I say Meh. Cassandra Clare is solidly on my "B" list, and likely to remain so.
I was charmed by Jem, tolerably interested in Tessa, but just couldn't warm up to Will Herondale. The attempts to make him mysterious and tortured only made him annoying.
I listened to this book as an unabridged audio, and will likely give the next in the series a go, as even B list authors are worth the time to read.