Are you aware that the Library of Congress is now archiving your tweets? The process is not totally set up yet and it is not availble to everyone at this point, but eventually it will be available for research.
The U.S. Library of Congress said today that it has completed a process of collecting a full, ongoing stream of tweets, and that it has begun work to archive and organize more than 170 billion tweets.
Under an agreement struck between the government institution and Twitter in 2010, the microblogging company is providing the Library of Congress with a full stream of all public tweets, starting with 21 billion generated from between 2006 and April 2010, and now supplemented with about 150 billion more posted since then.
If you are interested in reading the white paper on this update, here is a link to the pdf file...