I think there is one thing about self-driving cars, that is not yet in the collective minds of people just yet: if cars can move themselves, we could sleep, work, live in cars without human intervention. We could even recharge doing that. We also don't have to be in the car while the car is driving. As a consequence, we my see a whole lot of new challenges: E.g. in NYC parking is prohibitively expensive. I could see people being dropped by their Model S, then the car starts to cruise until the car is called back to the front door. Imagine what this would do to traffic. Also, if you imagine the loitering / camping / stopping laws we have in specific places - if we think this further to self-driving RVs, will we have places where not "auto pilot is allowed"? What kinds of new problems (and thus new laws) do we see coming with self-driving cars?