Will limit this to places I've lived or worked:
Boston: forget the Hav-had yahd stereotype, this is very much the working class city. Also very, very provincial (your friends there -- most of whom grew up there -- introduce you to their other friends, who are all just like them).
Ohio - people here hate being called "middle America," but they are (which isn't bad, some of the nicest people I've ever known were from the state).
Northern California (San Fran and related areas): full of people who aren't from there, so hard to generalize about the demographic. Not as trendy and current a place as people there like to think, a lot of the adult population is stuck in 1972.
New York: As provincial as Boston, but in a different way. Those who grew up here are proud of that and their attitude, which starts off being amusing but gets stale (like their behavior) very quickly. The more intiguing segment are those who moved here, which covers a lot of ground (every variant of the third world plus a universe of professionals attracted by the employment opportunities). I fall into the latter segment, and even though it's been 15 years still haven't deteremined whether I do or don't like being here.