why open access is good for libraries

The Open Access glossary page leads to all sorts of wonderful other pages including this one: “The (Refereed) Literature-Liberation Movement” with a longer article linked at the bottom “For Whom the Gate Tolls? How and Why to Free the Refereed Research Literature
Online Through Author/Institution Self-Archiving, Now
” The implications for libraries and librarians are obvious. Can anyone say “serials crisis”?