I like the vision of future urban transportation laid out in this article from Atlantic CityLab:

My utopian vision of how this could play out is to rededicate a lot of space in cities that was de facto applied to cars in the 1950s, after the death of the streetcars and the explosion of expressways, over to active transportation. Cars entering city limits would have to be autonomous or switched to driverless mode, as these will be deemed safe for all users of the transportation system and will operate in much less road space than drivers need now. (As a reference point, auto accidents are the leading killer of young people worldwide.) Parking needs could decrease dramatically, too, as most autonomous vehicles will be on-demand and active, compared to the 95 percent of time that current cars sit parked. We would have a transit backbone consisting of heavy and light rail/streetcars, and regional/arterial buses. The rest of the network and space would be slanted towards walking, bike-share, and other alternative modes.

I don’t necessarily think this is a “utopian vision”. I think a lot of it is just going to happen and is already happening. Enormous amounts of space that have been devoted to car maneuvering and parking are going to be available for other uses. The question is, are we just going to let all the space sit there or have a good plan for what to do with it? Some of it can be used for housing and economic activity, some for parks, wildlife habitat and movement corridors, and food growing, and some for managing water or harvesting solar energy. And of course, combinations of these are possible. But we do need to have a vision and a plan, which some can call “utopian” if they so choose.