Huh. Never lived in Ann Arbor or Detroit, just visited/had friends and family who lived there. My impression of Ann Arbor is that it's a college town where the population is relatively insulated from the surrounding community, unlike Boston where the colleges are heavily connected to local industry and so on. Everyone I've known from Detroit is an activist of some kind, so I probably have a biased sample set. But based on that I'd say "no", whereas I would definitely lump Cambridge in with Boston or Berkeley/Oakland in with SF.