So someday your old CDs may wind up in a museum or library being preserved. That is if we can straigten out the copyright laws and allow works that are no longer actively protected by the copyright holder to be preserved and placed into some kind of commons. I presume that recordings or data that is still commercially viable will be moved to new formats by those making money from it.
Curators at the University of California at Santa Barbara's Donald C. Davidson Library have digitized 6,000 late 19th-century and early 20th-century wax and plastic cylinder recordings -- precursors to the flat record. The audio, which includes ragtime hits, vaudeville routines and presidential speeches, encapsulates history with crackles and hisses, but archivists say preserving the sounds now is vital because the cylinders are deteriorating.