Autonomous cars will see their use more in senior population or people with hectic schedule. A car enthusiast will always take control of that steering wheel, period. Moreover people with disability will also be roam around the town more easily!
I think it's only the "Transition phase" which will be the most difficult, once there are more AVs on the road, Road casualties will come down and AVs will be more safer than human steered cars. We also need a device which could detect other similar vehicles on the road, so they could see each other easily, which means more useful data and better communication.
Now it's a matter of time before terrorists find their way into it and start their brutal activities. It's not 1990 anymore but the hackers community is always bigger than developers , so there is a possibility of terrorists getting hold of this tech to kickstart their business in the new world.
