The map itself is very innovative, allowing you to drill down to different projects by geographic region whilst the visualization dynamically re-arranges itself accordingly. I especially like things like this which allow meaningful interaction without detracting from what it is trying to achieve – something I hope I can carry through with my visualization project this year.
If you like this then you might also like to take a look at Netscan which is another good project that looks at mapping hierarchical relationships of Newsgroups on the Usenet. Variations in colour indicate a change in the number of posts for this month compared to last month.
An aside: If you like photography take a look at ‘Small World Gallery‘ which focuses on the fascinating art of photomicrography. The images were captured through a microscope and are quite incredible to look at.