From the School Library Journal blog:
You can read Doctorow’s full review on Boing Boing. He’s absolutely right to say that 7th Sigma could have been marketed as a YA novel. Perhaps length and the occasional profanity? Perhaps the unexplored origins of the deadly bugs? Or maybe the publisher did not want to exclude the author’s many adult fans.
Readers may be disappointed that the origin of the bugs is never investigated; neither are the other mysterious creatures that seem to collaborate with them. But add a sense of humor, genuine affection among engaging characters, and a grumpy mule sidekick for an adventure that is a natural for teen readers.
–Angela Carstensen, Convent of the Sacred Heart, New York City
Let’s just say the “origin of the bugs is never investigated” in this book.
Here’s the whole thing.