Are you referring to the little smart cars of today or some next generation product?
Im talking about self-driving cars. They won't have to stop at red lights, because it'll time intersection approaches so that cars are crossing from all directions in an interleaved manner. It's going to be a huge advancement.
Why use mass transit that is bound to a track, when you can have a transportation pod take you anywhere you want?
Just waiting for those techies in San Fran or Japan to figure it all out for us..