I'm really enjoying this series. Definitely getting down and gritty with what Clojure is really capable of (and all the other languages he's tried). Of all the articles I've read on concurrent programming and the languages that promise new ways to handle it, I find the Wide Finder series the most pragmatic and concrete.
I wouldn't say that the article gets down to the nitty gritty of what Clojure is capable at all. It's a great series about a high profile hacker having a go at what I think is a great new programming language.
For a down and gritty analysis of Clojure optimization you're better served reading Christophe Grand's posts. Or even my own fast but butt ugly optimization of Uncle Bob's Jarvis March- http://github.com/swannodette/convex-hull/blob/master/convex... where I use macros to inline everything.
