My prediction (I'm well aware this is worthless, as nobody cares about random-internet-guy's predictions enough to follow up) is that there will be a handful of cities that will try their best to orient themselves around self driving cars, and like the cities before them that tried to orient themselves around cars, they will fail. Most of the fanciful predictions from self-driving car futurism are incredibly naive and fail to take into account basic facts about how cities function from a systems perspective.

1) Traffic will disappear because cars can stop faster and travel close together. At best there are a tiny minority of driving scenarios where driving closer together or stopping quicker are the system bottlenecks. Rush hour traffic is not one of them. At best, you will drive faster on highways, but that will just get you to your exit faster, where you will spend more time waiting than you used to because intracity bottlenecks haven't changed. Traffic lights will still continue to make tradeoffs between latency and throughput, and self driving cars can't take away that tradeoff. And cars will continue to drive slow enough to stop for typical city obstructions (like cyclists, pedestrians, etc.), even if they have a few milliseconds faster of a reaction time. And you're still going to have typical rush hour volumes of people coming from multiple different places converging on a single area.

2) Haven't you seen the simulation where self driving cars don't need traffic signals anymore cause they can drive right through without stopping or hitting anybody? Guess what, it's a simulation...one that conveniently ignored almost every other relevant factor about how the world works. Like pedestrians. Dogs. Joggers. Cyclists. Handicapped people. Gridlocks that happen due to bottlenecks on perpendicular streets. Street protests. Weather conditions. In fact, the only way this idea feasibly works is if you are in a remote intersection in the middle of somewhere so unimportant that it doesn't have any other obstacles or traffic types, in an area where non-driverless cars are banned. And guess what...those situations get along quite fine with traffic lights.

3) But you won't have to circle around the block endlessly to find parking! Actually, your situation isn't much better, and if you see a rise in commuting by cars it could get much worse. Your traffic lanes will be continuously blocked by people getting in and out of their cars. Think of the airport arrivals and departures loops...nobody there has a need for parking, and yet still they are a traffic nightmare because everybody is either getting in a car or getting out of a car, and you have cars blocking traffic looking for their specific passenger, and you have cars circling around the block anyway because there is nowhere to stop legally.

I could go on and on. Traffic is the external manifestation of a system that is far more complex than streets with a few bad drivers clogging shit up. It is a manifestation of the interaction between cars and non-cars, economies and the humans that contribute to them, all with different goals and objectives, all trying to use a shared but very scarce resource. It isn't going away. Ever. The best you can do is find ways to move more people through it faster, and from that perspective the geometric reality of an automobile is grim. No matter how optimized for ommitting the driver it may be, a car will always take up exponential amounts of space compared to public transit systems.

But that isn't a reason to not pursue them. They should still be pursued on safety grounds alone. They just won't answer your prayers for a traffic-free city.