Read the article by John N. Berry III in Library Journal.
Here's one snippet:
"Our catalogers began to disappear with the takeover of that function by OCLC, the nonprofit that aspires to be a corporation in this brave new retail library world. The standardized result of the effort is bypassed by patron and librarian alike, as they turn to the more friendly Amazons, Googles, et al., for the less precise, more watered-down “metadata” that has replaced what used to be cataloging. Apparently, users don’t miss the old catalog, except as a familiar artifact, which is testimony to how low this dumbing down has taken us."
(Library Link of the Day)