Nowadays most library automation systems use keyword searching for all types of searches, Whether searching for titles, authors or subject headings, the results displayed are those which have the words the user searches on in the particular field they have chosen to search. (The default for most catalogs being a general keyword search, of course, one does have to select a particular type of field to the get specific results for that field, something librarians need to continually stress to their patrons.)
One result of this is that the older lists of titles, authors, subjects, etc. which used to present themselves as the initial search result, are no longer so obvious to the patron. In the Follett Destiny catalog, for example, the patron needs to click on a very small link which asks "Browse subjects?" to get to that list. My guess is that most patrons don't know what that means or bother to find out. One more opportunity to educate when we get the chance.
Because of this keyword default in searching any field, one thing I've begun doing in my cataloging practice to to put multiple subject headings where one used to do. Here's an example: instead of Sports--History--Great Britain, I make two headings: Sports--Great Britain and Sports--History. If the patron searches using the terms "great britain history sports" or "sports history" or "history sports" or any of a number of other combinations this title will appear in the results list. In the past with a strict alphabetical listing of subject headings it wouldn't have been as easy to get this item in the results list except through a full keyword search. I definitely like the new keyword searching capabilities of the catalog but it can also create traps. More on that next time.