I really cannot express how compelling a read I found this. There were times over the weekend where I resented going out and having to be away from reading. I had two successive book hangover days because it was so hard to put down at night. This book has given me a new benchmark for gripping writing; I suspect I'll not find anything to challenge it for some time, if ever.
My big hangup: some of the human characters. And not because they were awful. Well, of course I didn't like them being awful (natch); what I didn't like was their terribleness being so one-dimensional. I actually resented being emotionally manipulated in such an unsubtle manner, and found myself angry at both the author and the characters in those moments. The baddies from Gann, however, felt more properly developed. Not perfectly, some were just as poorly drawn as the humans, but at least I was (and still am) curious about the main bad guys, even while I was repulsed by their actions.
I sometimes also found myself hugely frustrated by Amber. She's strong, and independent, but that's not a good thing (at times). That sounds, oh I don't know, anti-feminist or like I'm victim blaming, and I suppose I may be. I mean, I suppose you can do or say anything you want in a survival situation, but there will be reactions. How you approach the matter, uh, matters, even more so in a desperate survival situation. Shorter version:
The Last Hour of Gann is an amazing read. One well worth the time investment, and one that I'm already thinking of reading again. Very highly recommended.
Warning: the main characters have some truly awful things happen to them, Amber especially. There are also stories told of some pretty brutal events. This isn't a story for everyone.