The State Library of Ohio has just released a Request For Proposal for an Open Source Statewide Resource Sharing System (Pdf).
Their summary page (which will soon contain an F.A.Q.) states that
The desired product would provide a seamless resource sharing solution, developed and released under an open source framework, in an environment of disparate integrated library systems (ILSs).
Looking briefly through the document, it looks to me as if the closest software in the library world is the Open-ILS Evergreen project, which is the platform for Georgia Library Pines system. The largest challenge might be the system’s need to communicate with a wide variety of existing ILS platforms.
The timeline is ambitious: Proposals are due by the end of January; a vendor will be selected and contracts signed by mid-March, a test system will be in place by September, and the system as a whole will go live in February 2010. Wow.