During the years I lived in D.C. I repeatedly heard, "I like New England (or Boston) but the people are not friendly." I was somewhat defensive until I traveled throughout more of the U.S. and realized that folks in other places are indeed friendlier. I do think it's based more on "Yankee reserve" than friendliness. For example, in a Boston restaurant you will never overhear the conversation of nearby party. You will in New Orleans. On the other hand, when you sit down at your table in the French Quarter the adjoining parties will say, "Hello" or, "How are you?" That will never happen in New England even if you make eye contact.
I'm not defending the criteria or finding of the survey but have enjoyed the responses the thread generated.