The thing is, I'm not so sure I love Clary. Jace seems to have gotten the brunt of Clare's efforts in characterization, leaving the heroine flat, passive, and with not a lot to be said for her. Her reactions bother me a little -- everything that she should be worried about washes off her so easily: her mother's kidnapping, the guilt she should have from their last discussion together, her abandonment, the fact that her life has changed entirely. She takes it all in stride, but this isn't written in a way that makes me think she's a strong heroine who doesn't let her problems get in the way of her goals -- I just think these things slip out of her mind or worse, don't occur to her.
I hope this might be rectified in the next book, but if you take the City of Bones by itself, Clary comes off as someone who should be a secondary character. As a heroine, she isn't too memorable (except that she's got a similar name to the writer's so I suppose I won't forget it too soon).
Also, perhaps it's because things are mostly from Clary's viewpoint, but the prose is hardly anything to get excited about. If you like straightforward (and occasionally awkward, I have to say) descriptions of events and places, this should be for you.
Still, the book has a bit more going for it than that. Jace, as I said, is awfully entertaining, and so is the dialogue. I'd prefer reading this if it were just about Jace sassing around and stabbing things, but things are the way they are. As for the plot, well, I'm a bit sick of vampires and werewolves -- can't people get a bit more creative with their supernatural specimens? -- but I appreciate the effort Clare's put into the Shadowhunter society. It's fascinating, speckled with bits of angelic lore and other myths, though I sort of wonder that the Circle could be so prejudiced against half-bloods when they themselves are half-mortal, half-angel. Huh.
And all right, let's go to what probably was the main controversial point of the City of Bones: so there was a curveball to this book that I did not expect, but I am fairly certain that this will all be cleared up as a bit of misunderstanding in the next few books. If you've read this book, you obviously know what I'm talking about. Props to Cassandra Clare for having the guts to tackle this sort of issue in a young adult book, and here's to hoping that she doesn't run away with it in the next title.
Conclusion: I'm on the fence about this book. This is a polarizing series, and maybe I'll find out which side I'm on after I read the next title.