Karen Schneider's post (How OPACs suck, Part 1) on the ALA TechSource blog says exactly what I've been thinking for a long time and what some library professionals still don't want to see: Catalogs must be user friendly! Instead of complaining that patrons don't use the catalog or don't use it correctly, they should wonder why they don't and then do something about it.
"They don't know how to search, we have to train our patrons." NO! Patrons don't want to learn how to search! They want relevant results when they type a word in the box, just like they get with Google or any other search engine.
Update: More John Blyberg on social OPAC's.
Update: A related view on information behaviour on the library’s Web site, with its dozens of user interfaces, search protocols, and limitations that confuses the student who is used to the clean and simple Google interface.