From their newsletter:
We're excited to release a new and addictive feature, "Common Knowledge." Basically, we've added a slew of fields to every author and book page, so anyone can add book awards, character names, biographical details on authors, book descriptions and more. It works like a wiki -- any member can add information, and any member can edit or revert the changes.
See the blog post about it.
I can vouch for the addictive part of it. The appropriate game is to identify a place where authors live (e.g Ann Arbor, MI) or a university they have gone to (e.g University of Michigan) and work your way through the world of LibraryThing filling in the gaps in their data. The easiest browser to see where the new data is coming in is the gender list; see new male, female authors.
Visibly missing is only an RSS feed for each of the new common knowledge pages (should be easy enough to do?). The authority control problem is making sure that all of the various variant ways to enter city, state, country get properly sorted together; is it "Ann Arbor, MI" or "Ann Arbor, Michigan, United States of America"? Autocompletion helps here.