Mapping User Metro Concentration by IP Address

I just posted this: http://www.goldb.org/geo_maps

It is a tutorial/example showing how to create a geolocation mashup by generting HTML/JavaScript code from a Python script.  The resulting code is an HTML page with embedded JavaScript that you can open with your browser.  It works with the Yahoo Maps AJAX API to plot markers at specified locations.  I also explain how this technique can be used to create a [near] real-time map of user concentration based on IP addresses.

... feedback welcome.

It generates cool AJAXy eye-candy like this:

and this:

Since I use the AJAX control, the rendered map has a zooming, panning, dynamic, tiled interface.  Pretty Slick.