reduce traffic

From this article:

Using radar, cameras, GPS, sensors and wireless technology, cars will be able to “talk” to each other and navigate safely by knowing where they are in relation to other vehicles. And connectivity will mean they can communicate with objects like traffic lights, too.

Result? Smoother traffic flow, an end to traffic jams and greater safety, as it would eliminate the frustration and dangerous driving that’s often triggered by sitting in heavy congestion for ages.

Essentially, cars communicate with each other and smart grids to self-organize their own routes in ways that minimize physical friction.

Theories on how to best organize these grids are still developing.

increase access for people who currently can't afford cars/insurance

IMO the first step will be making our public transportation driverless, which should reduce the cost. Furthermore, various Zipcar-like services should be able to offer "subscription" services for people. Subscriptions will obviously vary in cost, but they should prove fantastic and cheap alternatives for people like me that A) live in big urban areas, B) can't afford parking/insurance costs, C) find it inconvenient to own a car in the first place and don't like driving in congested downtown areas.

Although there isn't likely to be a massive reduction in cost unless we can find a way to efficiently exploit renewable energies for transportation.

I personally think that the equivalent of "bitchin' cruise control" is being oversold as the equivalent of "magic."

I can understand that perspective. I think it's healthy to be so critical, as we have had many embarrassing technological failures in the past. But we have cars on this planet right now that have driven for hundreds of thousands of kilometers in real-conditions without getting into an accident once.