Librarians are apparently getting quite concerned about DRM, and what it means to their ability to archive copyrighted works and lend them to multiple patrons. The British Library, for one, is concerned that excessive use of DRM could cause several problems, including limiting their ability to lend digital media to users.
Libraries currently have privileges that allow them to copy and distribute copyrighted items. But unless publishers produce unrestricted versions of digital material for libraries, they won't be able to exercise those privileges. Another concern is that, as technology advances and various software formats eventually become obsolete, copyrighted works can be lost if the technology is rendered useless before art moves into the public domain.