I enjoyed reading the article but don't really agree with quite a bit of it. I do agree that single individuals or very small teams most often make great breakthroughs, and that languages like Java do yield more "fungibilty."

I don't really agree with the Lisp-centric discussion because I have worked with many fine programmers who used several different languages. The right person makes a bigger impact than language selection.

As far as productivity goes, building a web portal in rails is far faster than using Lisp, and in my opinion will yield more maintainable code.

That said, I am using Common Lisp a lot right now because I am working on a book about AllegroGraph. (BTW, one good "home" for Lisp is back end services.)