I can see these replacing some urban roads first, rather than highways, simply due to the smaller scale. You could easily do a couple of pilot projects on some smaller, shorter urban streets. Also, their smart functionality will really come into play when you've got intersections, pedestrians and cyclists to play with.
As for encouraging car transport and BAU, I think personal transport is here to stay, until cities are rebuilt to be near walkable or bikable, with a very convenient electric tram system or something. But we shouldn't be anti-car per se, we just need to force the transition to electric cars, and at the same time force the transition to renewable electricity.
Google's driverless cars (
http://googleblog.blogspot.co.uk/2014/05/just-press-go-designing-self-driving.html) and an evolution from there, could massively change inner city transport, I see it allowing the operation of a subscription paying taxi/bus service replacement, with pay as you go options as well, all tied in to an app to call a car to your location, save favourite locations, routes etc. Private ownership of your own personal one if you like, but for many people, especially in cities, it might not be required. It'd be like an on demand taxi service. Buses could also join in the automation, and do the main busy routes still, particularly in city centres and where the cities are laid out in blocks and other patterns that lend themselves to convenient bus routes. Electrify the buses of course.
Anyway, there will still be lots of people wanting to go on various journeys, and it will need to be convenient, so don't write off roads just yet, just rethink the way we use them, and what we use on them.