The premise of this book - a near-future exploration of the government sponsored development of a technology for mind control - is very promising and I got the sense that the author put a fair amount of research and thought into making it convincing. In the end, though, the author is not entirely successful, either as a gritty, action driven thriller type a la William Gibson (the rather simplistic, somewhat naive ending; convenient deus ex machina abilities for Natalie and Bobby X) or as a more character driven piece (the interestingly ambigious Mary Delany, who we seem to be encouraged to feel some sympathy for as a victim of her own ambition, is summarily converted to a cartoon villain and wiped out; Guskov, the lurking chameleonic menace, in the end does little more than unsuccessfully defend his own ideology and has no noticeable impact on the denouement).
All this is to say that the author chose a huge, complex subject which in the end she was unable to do full justice to: a lot of things are left unresolved, or are not resolved satisfactorily, in spite of the book's length. However, I was much more impressed by this book than some of her more recent novels, which are much lighter in tone and seem to have given up on interesting characters - rare and precious in SF - entirely.