I grew up in the South - I have to say most of us are friendly, a wee bit too talkative and we'd be more than happy to sit down and have a nice big glass of sweet iced tea with you
I remember my first trip to NYC and I was amazed at the rudeness. With more and more Yankees infiltrating our friendly areas (sorry Vooman :P ) I've really noticed people not being as friendly in ATL as they used to be. My girlfriend moved to Chicago about 15 years ago and always got her "friendly fix" when she came home. A few years ago she noticed the change
That's one of the reasons I moved to the hills - we're all still nice up here and I can't remember the last time I went to a store, grocery, pharmacy, etc. and didn't have a nice conversation with someone, had the door opened for me, waved to if I let them into traffic, etc.
It all depends on where you are