I went to go see Sebastian Thrun speak at Stanford about his team's winning effort in the DARPA Grand Challenge. Thrun described the contest as how to stay on the road for a very long time. It was not a general path-finding problem: DARPA gives you the route with a corridor you have to follow, as well as speed limits you have to observe for various parts of the course. Of course, DARPA didn't give perfect data. He showed a video generated from the data of Stanley driving through the most dangerous part of the course: the switchbacks of Beer Bottle Pass with a cliff on one side. DARPA's corridor was overlaid on top of Stanley's sensor data and it was easy to see that much of DARPA's corridor was actually over the cliff.
During training many traffic cones were "frequent victims of computer glitches," but Team Stanley was called "Team Boring" by the cleanup crew for their lack of incidents. The actual challenge was described as getting the data at 4AM, getting Stanley to the starting line at 6AM, and then sitting around drinking beer for several hours. The big moment came when Stanley passed CMU's Highlander as the CMU and Stanford teams listened to race radio. Thrun narrated the exciting finish for us: "[The head of DARPA] is waving his flag as if the car could see it."
Thrun said that they won mostly through luck given how close four of the teams finished. The speed limits set by DARPA for the various parts of the course were too conservative, so the cars were running below their full potential. DARPA also decided to make the course fairly easy. Asked if CMU would have won had they not had engine problems, Thrun answered, "In all likelihood, yes." Also, Team ENSCO had a faster average course time but flatted on "something really big CMU left behind" (the CMU part may have been a joke). Thrun felt that Stanford had better software than CMU and on a tougher course Stanford would have the advantage.
In the future, Thrun wants to try driving 65mph on 280, parking in a garage, convoy driving, and driving assist. Part of his motivation is to reduce traffic deaths, which a driving assist system could help prevent. He also feels that a fully automated system would change society by allowing you to use your commute time productively -- you could even drive to your destination, get out, and then send your car to go park in a parking garage farther away. These are still looking far ahead. In response to someone asking what it would take to drive at human-controlled speeds, Thrun related it to asking the Wright brothers, "If you want to fly over the Atlantic, what's missing?"