My thoughts on this, from back when I originally read it (yes, quite some time ago):
First, I was actually disturbed. That doesn't happen often. Pleasantly creeped out, grossed out, annoyed, disappointed (all too often), mildly sad or happy, those I get a lot.
Disturbed, not so much. It was a brief scene and a relatively mild effect--nothing as intense as reading "The Screwfly Solution" or watching the end of
Hannibal--but damn. I am not used to novels that can do that. I am impressed.
Second, it comes across as *intelligent*, which is different from simply smart in some way I cannot put my finger on. Very information-rich, and I am not seeing any of the talking-down-to-the-audience or playing up of shared assumptions that I usually spot in horror.
Worth picking up.