Yup. It was such a good talk, I assumed it had made the rounds among HNers that I didn't need to link to is. I assumed wrong.
It is a brilliant talk. The only part that he left out of the discussion, but is worthy of a talk in its own right is the notion of the community (formation and characteristics) as one of the artifacts that result from the constructs of a language.
(a thought provoking talk for those who haven't seen it)