It is, of course, a flawed book. Caitlin writes a livejournal which sounds nothing like any teenager's livejournal I have read. The AI character, absorbing all the knowledge of the www, is unfazed by linguistic differences or by the difficulty of telling truth from fiction, and deduces middle Canadian morality from Project Gutenberg (and I hate cute disembodied artificial intelligences almost as much as I hate cute robots). There are two subplots, one about China and one about intelligent apes, which go nowhere (they may be setting up for the two coming volumes of the trilogy, but I must judge this volume on its own).
Most damning, Caitlin, whose life has been utterly constrained by her own disability, does not even notice her father's somewhat different disability until two-thirds of the way through the book; which seems utterly out of character for the sort of person we are told she is.
So, not surprisingly, this is at the bottom of my Hugo list so far, with two more to go.
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