Twitter is an enigma, no question. One of the under-appreciated uses is to examine the structure of the network of people using it — who is the center of attention, how is information passed along, what are the bridges between various segments? Is the community dense or is it spread thin? Since marketing, pr, and advertisising are all in the communication basis it sometimes helps to analyze the flow of information.
The recommended approach leverages social network analysis, the discipline focused on the structure of connections rather than the nodes the themselves. Long used in the social sciences it is becoming more important to marketing; particularly in the age of social media. A tweet, or an email, is a link between two people - looking at all of the linkages provides an overview of how a group of people interact.
For an interesting application here’s Mat Morrison’s analysis of the tweets among members of congress. John Culberson, the Republican from Texas, has the most influence as well as connections to the ‘other side’ via Neil Abercrombie, the Democrat from Hawaii. They would be on a short list of ‘influentials’.

