I think theres a chance it might not come to that, and Tesla hinting at their own Uber operation is very telling that maybe in the future, regular folks wont need to own a car. We'll just hit a Tesla app on our phone and an autonomous car will come to take us where we need to go cheaper than it will be to own a car.
Yeah that is the auto car utopia that people talk about. I think it can be a reality in major cities, retirement communities, college areas but I don't think we're just going to replace the entire fleet for a long, long time. People like driving, the feedom, the convenience, the open road. Now if the economics make buying a car a very poor purchase then it could go back to being a luxury item like when it was 1st invented. I think we're a long, long way from that though. 20+ years. Also, when scaled to that extreme it is kinda Orwellian so some of your big Gov't Paulbot skeptics may rebel.
@Chop....My guess is what you are looking for will come in the form of something that isn't a true auto car but rather can drive itself 99% of the time (this is already pretty far along tech wise, we'll see these by 2021-20223ish barring regulation BS IMO) So then you'll be driving and some censor/map/weather app will pull the car over and say you need to navigate the car going forward.
I probably didn't just describe that situation perfectly but it will be something along those lines. 99% automation will get here before full automation.