I, too, think you are right, about the growth of Madison, Alabama. That town seems like it's growth, at present time, is boundless and over the next few years will help assure that Huntsville, Alabama will potentially be Alabama's largest metropolitan area.
I know at one time, years ago, there was very optimistic talk about Birmingham becoming the South's newest and next "Atlanta" but that never materialized. Guess in the coming years we'll see if the talk and forecast about the Huntsville area becomes true.