Google's next driverless car goal? 1,000,000 miles

According to Brin, Google's teams have already amassed more than 1,000 incident free miles without driver involvement.

Up to now, Google's driverless cars have gone 160,000 miles, but with some limited human input. The company admits that there's been one fender bender, but attributed that to human driver error rather than Google's software.

Google would like to reach a point where it's legal for driverless cars to mingle with everyday traffic, but Brin said there's a lot of research and development left to do. Before the technology can be marketable, Google says it needs to be developed to need to a point at which human drivers can ignore the road entirely.