Well, it nailed my speech patterns. I was born and raised in the city of Chicago. The three cities it lists for me are all near one another in northern Illinois: Chicago, Aurora, and Rockford.
Wife and I both took the test, however midway she or I got different questions. I guess the questions change as you go along to help nail your base.
Same here it was pretty spot on with Rockford/Aurora IL but also threw in Toledo, OH strangely enough:)