My plan for this project is to cull blogs for popular (viral) topics and consider how and how quickly the news topic or video spread.  I'd start by indexing a few hundred blogs and then determine the  most popular topics shared between many of them.  Then I'd note the times each of the blogs posted on the particular topic and if they are linked together or to the original source.  I'm not sure how trivially the data could be acquired for this.  I also would like to have some sort of graphical display for the results.