The Library of Congress has announced that it is archiving every public tweet made since the service went live back in 2006.
Why you may ask? ars technica gives a pretty good explanation
There’s been a turn toward historicism in academic circles over the last few decades, a turn that emphasizes not just official histories and novels but the diaries of women who never wrote for publication, or the oral histories of soldiers from the Civil War, or the letters written by a sawmill owner. The idea is to better understand the context of a time and place, to understand the way that all kinds of people thought and lived, and to get away from an older scholarship that privileged the productions of (usually) elite males.
The LoC’s Twitter archive will provide a similar service, offering a social history of hipsters, geeks, nerds, and whatever Ashton Kutcher is. As Twitter continues its march into the mainstream, the service really will offer a real-time, unvarnished look at what’s on people’s minds.
And here is more from the Library of Congress itself.