GoogleBooks is a Ruby wrapper that queries the Google API to search for publications in the Google Books repository. It is authored by Zean Tsoi and provides additional methods and search options. Queries return results, each with their own set of attributes that can be individually configured.
EBSCO announced that Sweden's Stockholm University has selected the EBSCO Discovery Service (EDS) which includes custom integration of the EDS API into the institution's library software platform. The University was looking for a reliable search and discovery solution that would be easy to integrate with the existing library software platform.
Folks interested in "open knowledge" should check out CKAN (Comprehensive Knowledge Archive Network)
CKAN is the Comprehensive Knowledge Archive Network, a registry of open knowledge packages and projects (and a few closed ones).