The laser beams on the Tele Atlas vans scan each building on the road thousands of times, creating a three-dimensional model of the neighborhood that, when matched to photos from the high-resolution cameras, can be used to re-create a realistic cityscape.
The three-dimensional environment allows movement in any direction on foot, and the cockpit flight model allows you to roll and strafe in any direction.
The complicated business-model considerations for driverless cars have already kicked off an intense game of three-dimensional chess, and Google could obviously lose.