I loved it. I mean, it also took me a long time to read, but that had nothing to do with the quality of the book. That was just me being too freaked out to continue, because I could recognise myself far too much in these teenagers. I grew up in the same general area, with the same kind of skills and abilities, and it was frankly terrifying to watch what they had to go through. Everything was very well described and certain things — especially the descriptions of the cold itself — felt visceral, in the best way possible.
Adding to that, it had several great characters and more intrigue than I had expected. I loved the dynamic between the characters, and the fact that everything wasn't just black and white. Some people behaved poorly, but that didn't always mean they were evil. My favourite characters in the book by far were the old villagers who just... kept on living, almost as if nothing had happened. I loved them, mostly because I can see so much of my older relatives in them.
A great book, definitely, if also frightening.