Have a look at this excellent blog post on the Open Access update session at this year's Libraries@Cambridge conference:
http://libatcam.blogspot.co.uk/2013/01/parallel-session-1b-open-access-at.html
This session was thoroughly informative about open access at Cambridge and provides excellent background information. Thanks
to the conference organisers, the speakers and the live blogger who
have all helped to disseminate this important information.