When this really does become a thing there are all kinds of interesting points to iron out
- Accident liability. Are you responsible if your car is at fault in a crash, or is your car's AI?
- Security. The possibility of people being able to tamper with things that drive you around is pretty scary (especially if you're a person of note).
- City centre traffic. London and New York are bad; Mumbai and Beijing are worse. I'd worry that any AI risk averse enough to avoid an accident would grind to a halt without a significant amount of rather scary real world testing.