Here's a quick and dirty script for parsing the site and rendering the colors in an RGB scatter plot.

https://gist.github.com/ginkgo/9656285

edit:

There's a couple of interesting things to see here:

* There's a clearly visible diagonal axis of the shades of grey.

* There's a cluster of colors around the default orange value.

* The "pink corner" of the color cube is very sparsely populated compared to the other ones.