Ort.

Bit.ly says that the data flow they are seeing is so massive that they are getting very good at predicting the number of clicks a link will get in the future. They look at acceleration of clicks as well as the source (Facebook, Twitter, IM, whatever) and whether people are clicking that are outside of the social graphs of other people clicking. In other words, you could say that Bit.ly knows what will be on the Digg home page tomorrow.