Ok, I think it is now safe to talk about the Harvard Law Library Innovation Lab (LIL) LibraryCloud! The LibraryCloud is an Internet open service (via a web API) to access library data. The backend is a mix of relational data store and Solr instances. It currently contains bibliographic information and de-identified aggregated circulation information. The goal is to both make the information available as an open service and to encourage people to build applications on top of it. Beyond making the basic data available, the LibraryCloud is also looking to make connections in the data visible (we call them “neighborhoods”). For example, all of the books written by an author is a neighborhood, but so are all the books in a subject area and so are the books within a certain “distance” of a call number.
You can see a more detailed explanation of the LibraryCloud here