Visualization Project and Google Maps

This semester I've been tasked with finding a reasonable project for my advanced graphics course.  A small part of me wanted to use a basic physics engine, get some nice graphics and make my own version of angry birds or something, but I decided I'd go with something else.  Maybe something to do with the social world...

I switched my plan to a visualization of individual tweets on top of something like Nasa World Wind, but as I began to investigate it, I found it very useless. A visualization of an individual tweet isn't nearly as cool as a visualization of many tweets over time, which brought me to my final idea (with the help of Tim)...

I think I'm going to do a visualization of twitter geographical data on top of google maps (or google earth).  This way I'm aggregating the data before showing it to the user, which should be much easier to understand.  My plan is as follows:

1. Divide the map up into a grid.  For starters I will just do this on a single major city.
2. At different zoom levels the data will be regrouped.  This way when a user is looking at the entire city it should show them a set of grids and as they zoom, the grids will become more detailed.
3. Provide (in tooltips or based on click events) details about the data in the grid they're selecting.
4. Provide some kind of coloring of each grid so that a user can tell where the most tweets are coming from.
5. Weight the tweets based on how old they are (e.g. a tweet from yesterday doesn't influence the coloring as much as a tweet from today).

This should provide an aggregation of data that shows where the most geo-coded tweets come from.  The plan is to architect this in a way that if it works well that I could expand my search to include a larger area.

--Colt