Sebastian Thrun, Professor of Computer Science, Stanford, talks about the different challenges between previous Grand Challenges, and the current Urban Challenge. Thrun also discusses the financing behind the car, and how they received most of their money.

From wikipedia.org:

Sebastian Thrun, (born 1967 in Solingen, Germany) is an Associate Professor of Computer Science at Stanford University and director of the Stanford Artificial Intelligence Laboratory (SAIL). He led the development of the robotic vehicle Stanley, which won the DARPA Grand Challenge in 2005 and brought Stanford a two-million dollar prize. Thrun is also known for his work on probabilistic programming techniques in robotics, with applications including robotic mapping. In recognition of his contributions, Thrun was elected into the National Academy of Engineering in 2007.