Quoth Wikpeida: "In August 2011, a human-controlled Google driverless car was involved in a crash near Google headquarters in Mountain View, CA. Google has stated that the car was being driven manually at the time of the accident. A previous incident involved a Google driverless car being rear-ended while stopped at a traffic light."

http://en.wikipedia.org/wiki/Google_driverless_car#Incidents

It's still in the testing phase sir... and i am not sure what you expect when you question no has rear ended the cars??? you want a mile by mile report from google isn't it too much to ask for from a company which is just testing its new product focusing on making it a more safe car to use. you want them to maintain a driving book for this i don't wanna go on with this... let hope they manage to make a really nice and safe car in the end.

Number of miles don't matter much if the driving conditions are similar.

I'd rather have them say, we can encountered 100,000 different conditions (and combinations) and we know how to react to them.

How about oil slick James Bond style?