Conde Nast Traveler has announced their annual 10 friendliest and 10 unfriendliest Cities. LINK
Detroit is getting better, they went from #4 unfriendliest to #6 unfriendliest!
The City that I work in is a tourist town so people here tend to be very friendly. The City that I live in is a different animal though. The friendliness here is more about how amazing the City is and actually wants new people to move in. Not just one group, but everyone. They also seem to go out of their way to be polite and respectful.