Wow, that was quite a climax.
The writing leaned way too hard on extinction-level slaughter for my taste (an enemy doesn't have to butcher nearly everyone on the continent to be a legitimate threat), but the story wound up being surprisingly solid and satisfactory overall. Though it caused me some frustration along the way, I like in retrospect that we rarely saw beyond Vivian's awareness of the present moment. That approach kept things suspenseful throughout and especially in these last two chapters. It cleverly allowed for white-knuckle, last-second rescues from impossible situations by what only seemed for a moment like unjustified deus ex machina.
The story's done that all along, keeping us one or two steps behind an understanding of the forces, plans and loyalties in play. This allowed the threat to scale up as the story progressed without stretching credibility. I also liked seeing Vivian grow and learn from her experiences in a realistic, small-scale way. While she remains a somewhat flawed heroine, noble but overly stubborn and idealistic, she's come to understand the consequences of her decisions and seems better able to work with others in order to achieve her ends.
Plus all the eye candy in the world. Bravo!