A loooong time ago, I showed the agu10 archive as a graph, here's the same for the combination of agu11 and agu2011. I mentioned already about the upper/lower case issues (excel is oblivious but my graphing program cares) - this is all lower case (I first tried to correct but kept missing things so I just used Excel's =LOWER()). I also discussed how I got the data. I'm going to have to probably go back and do this for 2010 if I really want equivalent images because 1) I only kept the first @ (this has all the @) 2) I don't believe I did both 2010 and 10 so I probably missed some. For this image I did a little bit of correcting. One twitter name spelled wrong and quite a few people using the_agu or agu instead of theagu. I also took out things that were like @10am or @ the convention center.
I made this graph by taking my excel spreadsheet that was nicely username first@ second@ .... and copying that into Ucinet's dl editor and saving as nodelist1. Then I visualized and did basic analysis in NetDraw.
The largest component is 559 nodes of 740 and this time you don't see that breakdown where the people who tweeted @NASA didn't tweet @ theAGU. There were 119 isolates and other components with 2,3, and 10 nodes:
eta: oh yeah, one other little fix. I took out random punctuation at the end of user names like hi @cpikas! or hey @cpikas: or well you get the idea