One day I went to iGoogle and saw this little story. (I saw it but did not follow the link.)
Yes, in America, extroversion is a valued commodity. In the UK, it is the opposite; if you are extroverted, you are not normal.
I'm introverted. Maybe I should move to the UK! Well, we did, back in 1995. But I'm too much of an American - in other ways - for it to have become home enough for us to have stayed.
I find it amusing that some people make money changing others' personality characteristics. Having said that, however, it is a good thing for us to work on our rough edges to move closer to the center from some of our extremes. I appreciate the Meyers Briggs test and how it has helped me understand myself and my spouse better. (If you haven't taken the test, you might consider doing so.)
And by the way, I never did find out what a "belt flip" is.