For the first 10 minutes or so, I was all set to dislike this story. "Not another alt-sex story from Vylar Kaftan..."
But then, I have to admit that it won me over with its optimism. I'm always a sucker for disaster porn, I guess, and I have to admit that an super-volcano apocalypse is a pretty creative way to go. I think Ms Kaftan did a great job drawing the reader into the story. While I still found the protagonist overly-whiny, I ended up relating to her, and I was rooting for her at the end. And really, who doesn't love a good wedding?
I do have some criticism, though. Overall, I felt the story lacked action and had too much exposition, i.e. "telling" the reader instead of "showing" the reader. I also personally found the idea of 3 unarmed women traipsing around in an RV, during a time of the complete collapse of law and order, to be rather unrealistic. In general, it felt like the people in story would have reacted far worse in a real disaster. If hurricane Katrina was any indication, you'd have looting, arson, murders, rape, and probably stressed out authorities enacting martial law and summary executions trying to impose law and order. I may be in the minority here, but I don't think Burning Man hippies, even trained in survival, would be equipped to deal with such a situation. It's one thing when you have a festival where similar people more or less want to be there. It's quite another thing when you have hordes of people sick, dying, and desperate trying to get what they need to in order to survive.