Calling google's digitization effort a card catalog is putting the
emphasis on the technical fact that a search engine doesn't ever search
the full text, it actually searches an index that has been built from
the full text. The interesting legal question at issue is whether the
law considers robots reading books to create indexes to be substantively
different from allowing humans to read books to create indexes without
infringing the copyrights of authors. There are arguments both ways. The
argument that they are different is framed in terms of calling the
digital instantiation of the book a "copy", while the argument that they
are the same is framed in terms of the process of creating the index.
Personally, I think authors, libraries and publishers will all benefit
from a legal environment where indexing is uninhibited and copying is
strictly proscribed (where copying is defined in terms of producing
functional equivalents of works- if a person can't read it, it's not a
copy).
Eric