Cool. As a matter of fact, about a week ago I tried to do something similar by trying to integrate Python with Minecraft. I actually did expose the full Bukkit API to Python (easy enough to do), so all its commands are available.

I didn't really like the "type your code in Minecraft chat"-approach many similar projects were/are taking (i.e. "/js myCodeHere()" in chat) and wanted a proper interpreter window. To integrate the Java-based Bukkit API with Python, I used Jython. The result is something similar as shown here: http://www.minecraftwiki.net/wiki/Pi_Edition

I've yet to put up a blog post or something, but I've thrown together a quick video of me playing with it (it's a bit slow so feel free to forward) here: http://www.youtube.com/watch?v=rI3PfgCSI7Y

I think something like this could really help in getting kids excited about programming. Back in the day, I started learning programming with LOGO http://en.wikipedia.org/wiki/Logo_(programming_language) , a quirky adaptation of LISP, but where you could immediately see your results drawn on screen. It's cool to see Minecraft as some sort of modern "canvas" for programming.