I gave my talk to the useR! 2011 conference this morning: The R Ecosystem. The goal of the talk was to show R in context: that the combination of the R project and its leadership, the R userbase, and the companies supporting and using R makes for a thriving ecosystem and is indicative of an extremely successful open source project. I also summarize some statistics from the R userbase survey from last week, and extrapolate (unscientifically, but the best I can do for now) to the size of the R userbase, which I estimate exceeds 2 million users. The link to the Prezi presentation is below; for best effect play it in fill screen (click "More") and note that the links to resources are clickable.
UPDATE: A PDF version of the presentation is also available.
Prezi: The R Ecosystem