Only in a limited definition of effective metro areas. There is a swath of extremely low population agricultural land that you must travel through to get from Ann Arbor to towns like Canton which are clearly in the Detroit metro. By some definitions, this would place Ann Arbor in its own metro. Another interesting factor would be the commuting ties between the areas.

> By some definitions, this would place Ann Arbor in its own metro.

This is why I added my parenthetical. I lived in Ann Arbor for several years, so I'm familiar with the area.