Wired magazine voices concern

That Japan is far ahead of the US in intelligent traffic management.
In Germany, BMW says:

Recently, at a test Track near Munich, Germany, BMW's Traffic Technology and Traffic Management group has been busy checking how management of traffic light timing could produce greater fuel efficiency and improve traffic flow. The group's engineers say they were able to almost double the fuel economy of a 530D test model from 22 mpg to 42 mpg by creating "green waves" for drivers.

This German city has already installed a wireless traffic net, using OnStar technology:

 A German city has developed a system of intelligent traffic lights that can tell drivers when the lights are about to change.

The creators of the system say it can reduce fuel consumption by up to 17 per cent by ensuring that drivers get more green lights.

The system, developed by Audi and its home town of Ingolstadt, can calculate a car's approaching speed to an intersection and work out, based on the phasing of the traffic lights, when the car will arrive.

The traffic lights then ' talk' to cars via their satellite navigation systems, telling drivers that if they slow down as they approach an intersection, they won't have to stop the car, idle and take off again. The technology can also calculate when a green is going to turn red and warn a driver that they risk a fine if they try to run the light.