Selectable Scatterplot

I'm playing with this code adapted largely from the very nice example from http://2011.12devsofxmas.co.uk/2012/01/data-visualisation/

The code remains a bit messy, as I am clearing out parts that I don't need and organizing the remaining code, so please bear with any slight disorganization.

This is best viewed by clicking the link to open this example in a new window so you can see the whole visualization.