I just wrote a two Yegge long blogpost on the performance of the Persistent Vector, along with some ways to speed the Clojure implementation a bit up. It's available on Persistent Vector Performance. For people not that interested in the details, it's probably best to have a look at the summary instead.

Latest (interesting?) blogposts:

I designed a quicksort implementation in Swearjure. It's completely useless, but is a proof of concept that Clojure is "usable" even if you remove alphanumerics.

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