Chaos hopes you haven't been thinking that this topic has been abandoned here at the Edge. Here's one very thoughtful fellow's opinion (Nate Hagens from oft-quoted The Oil Drum):
"The best places in the world will be the ones with a combination of the following things: the most social cohesion (strong reciprocity), the highest renewable infastructure, the smallest amount of energy required for basic human needs (food, water, shelter) (This means high degree cooling or heating locations lose points), a high biomass to human ratio, the best aggregate of human, social, built and natural capital. If you fall in the camp thats worried about nuclear war, a city in the southern hemisphere would be optimal, as they dont share air circulation with the north. A city near water and rail will have big advantages over one just served by air and road."
Chaos can't add to that, right now.