In Canada, at least, Americans have a reputation for being loud and rather obnoxious. I have an uncle in San Diego who fits that stereotype perfectly, right down to smoking a cigar! Of course, the loud part could possibly be attributed to hearing problems, but why break a good stereotype? ;)
I've had the chance over the past few months to spend some time in the U.S. in Missouri and Colorado. One thing that struck me immediately was how friendly people were. Walking down the halls of a place where I had never been before, practically everyone said "Hi" or "How are you doing?" or, in Colorado, "Howdy!".
Canadians, I'm told, have a reputation for being friendly, polite people. I walked into the office this morning, and had only one person say hello, and that was someone I knew. Everyone else was doing their best not to make eye contact in case they then had to say something.
Of course, some of the people in the U.S. who said hello could be serial killers and those who didn't in Canada could be the nicest people in the world. However, such a small, simple thing certainly makes me feel more "at home". Maybe it's owing to my small-town roots, maybe not... I don't know. Perhaps the places where I was staying were more friendly than others. Again, I don't know.
What I do know, though, is that it's something very simple to do and I'm going to continue to do it myself.