The site says it best:
"Digg Labs: A broader (and deeper) view of Digg
Digg moves very quickly, and has a great many stories submitted every day, so good material can sometimes fly by before you even know it. These interactive visualizations look beneath the surface of the Digg community's activities. "
I especially like the swarm - it almost seems like news is coming in organically.
A special request to Rahul D and karan to check it out, if they already haven't - that is.