There's been talk about integrating this functionality into Clojure. Incanter is an example of a project by someone who wanted to get primitive support for matrix math and has had quite a bit of success.
"How do you know I don't do my research by making provocative statements on public fora?"
There is something to be said for that. I would not have thought to Google for "R-like interactive environment, built with Clojure and Java charting and numerics libraries." But now that I know it exists, I'm pretty excited about the possibilities.
Wow, that looks potentially awesome. Certainly looks like it has the potential to compete with NumPy and R. Nice use of Clojure to tie together unrelated Java libraries with a useful syntax and REPL style exploration.