Mining twitter data

Who is the first reporter of the Mexico City earth quake?  I remember watching twitter second-by-second and @cjserrato was the first one reported the earth quake (the tweet id is 1630381373):

 

Mining twitter data is a huge challenge.  So far I have not been able to see many interesting data/text mining and data analytics around twitter data.  I have been playing the data lately, and here’s a thematic/topic graph I had – a visualization of all tweets of the last eight hours that are related to to “mexico city”:

 

You can tell that “Swine Flu” still at the center of all topics, whereas earthquake is clustered alone to the side.

Have you seen any interesting twitter analytics (by the way, I do not mean the twitter metrics or counters etc..)?

Jeff Clark of NeoFormix has a great set of application, the best I have found so far.  FlowingData is another one.