You lose *some* opportunities for serendipity, but you gain others. In many online catalogs, for instance, the authors, subject headings, alternative breastles, and call numbers are all links that take you to browse lists. Some of those you could have browsed in the main card catalog, but that would have required walking over to a different part of the catalog. And there was no way at all for library users to browse call numbers in the card catalog.
kkt My heart bleeds! Going to the main-entry card and following the tracings found there was a...
A greater loss of serendipity, IMHO, is that lots of the collections of most large libraries are now located in off-site closed storage. Users no longer just chance upon some obscure book that has been sitting there for 20 years that happens to address their need.
cp67-cms had a source *update* appliatiion called *update* that used sequence numbers on card images (default field in...
Yes, many research libraries that have discarded their card catalogs have filmed them first. It's a safety measure in case your conversion process missed something.
In LC's case, they haven't had the money to convert all the older materials card records by hand. They used an OCR process, which is better than nothing but there are some typos and some of the tagging is incomplete. Conversion by hand continues but won't be done anytime soon.