Not the OP, but the one full book I've read on the topic is Scott Aaronson's "Quantum Computing Since Democritus". It gets a bit laborious walking through the

Not the OP, but the one full book I've read on the topic is Scott Aaronson's "Quantum Computing Since Democritus". It gets a bit laborious walking through the entire "complexity zoo", but does a good job of laying out the general space in which quantum computers may (and may not, as far as we can tell) be useful.