This is a really interesting article on the Dance Heritage Coalition that shows the depth of digital preservation and the variety of information that we as a society give importance to and therefore want to preserve. The article states:

"Videotape has become the archival storage medium for dancers and choreographers and popular belief within this community has always been that information stored on magnetic media is permanent. Magnetic tape has provided a medium to record and replay our dance history at will, but magnetic media have a very limited life span and playback machines quickly become obsolete. As a result, irreplaceable tapes are in peril and the probability is real of losing forever many of the moving images that have become the collective memory of all forms of dance. The emergency is especially critical within major institutions and repositories, including all of the Coalition member institutions, where rapidly deteriorating videotapes represent a major part of many archival collections. (For example, the New York Public Library, Dance Division estimates that it holds approximately 40,000 videotapes, representing virtually every type of dance practiced throughout the world.)
With this crisis in mind, the Dance Heritage Coalition has closely monitored the development of digital technology throughout the past few years. In a report to the National Endowment for the Humanities in 1997, the Coalition identified a critical need for the preservation of moving image and audio materials, particularly for dance recorded on videotape. A Technical Advisory Group was created in 1998 to guide and inform the Coalition in these matters. Drawing upon professional expertise in moving image video migration, the group proposed using dance as a model to address the complex issues surrounding the preservation of magnetic media.
Therefore, with funds from the National Endowment for the Arts, the Coalition called a meeting in July 2002 to design an experiment to determine the most appropriate method of transferring analog videotapes to digital for preservation purposes and using a variety of dance videotapes as the testing focus. In the case of dance videotapes, the digitization process will not only conserve the original object but will reduce the further deterioration of and provide access to rare, fragile, and vulnerable materials. By setting preservation standards, the outcomes expected from this project will have enormous resonance not only for the dance community, but for every major archival institution."

You can read more about the Dance Heritage Coalition at http://www.danceheritage.org/publications/dance_video_risks.html