I had the same thought at first -- next time, make sure the text is bold enough to be legible at 320x240. Once I maximized the vid it looked great, of course.
Very cool demo, this looks like an amazing tool (and I don't even know much about Hadoop!). One question -- it looks like you're skipping over the time it takes for the "illustrate" function to calculate your results. How long does it take for this million-song dataset?