Joe wrote about this already, but now the recording of John Chambers' keynote presentation from the useR! 2014 conference, Interfaces, Efficiency and Big Data, is now available for viewing thanks to Data Science LA. In the video, John dives into the history of the S language for which he won the ACM Software Systems award and which ultimately led to the R project, where John is a member of the Core Team.
Data Science LA is publishing a series of videos taken from the conference. You should also check out the interviews with Hadley Wickhham (Chief Scientist, RStudio) and Max Kuhn (Director, Pfizer R&D).