Datatypes and Protocols - early experience program (here, via @ajlopez) -- time to try the new features; there is even a build ready to be used
Rich Hickey's Clojure keynote from the JVM Languages Summit posted (here, via @cemerick) -- finally!!!
Moderately-deep dive on clojure refs (here, via @timbray) -- Tim Bray explores clojure a little more, this time the use of 'refs' and finds that if you try to process large datasets you might get some nasty garbage collection thrashing. He asks the community about what's wrong with his experiment, and the community responds... read the comments; some are very enlightening, like this cool (idiomatic) version by @technomancy