[seanmcdirmid]

I live in a mega city where taxis are cheap so I take the daily and avoid owning my own car. The big deal will be in cities like mine where parking is rare and expensive if found at all, while roads are extremely congested. Self driving cars solve the parking problem (which admittedly, taxis do today) + can use road bandwidth much more efficiently (which taxis cannot). In the end, I see all of these factors destroying personal car ownership in big cities. Now:

Cleanliness: this is an issue in taxis already. Sometimes I get into a taxi without window handles, but that is the government's doing.

Style: expressing yourself through your car sounds like a very American thing. Much of the world is not America, to say the least.

Status: this is the biggie where I live: those with money have to show off their Audi TT's and BMWs. Perhaps they will still own their cars, just like they do today (whereas many people just rely on taxis).

Practicality: my city already does not allow outsiders to enter within the 5th ring road during working hours (7AM to 7PM), while their is a lottery for "owning" a car with 20-1 odds per cycle. I can imagine that there will just be different vehicles for the country-side vs. the cities: the latter will be automated while the former won't be. You can own your country-side car if you want, but you can't drive it inside the 5th ring road given traffic unless it has a self-driving mode (to optimize traffic).