By today [5.Feb.2008] the Petition for guaranteed public access to publicly-funded research results to the EU, as sponsored by SPARC, DEff, DFG, JISC, SURF, and realized by Key Perspectives of Alma Swan, has been signed by 27.047 persons and institutions.
A statistics of how many from which country, professional field, institution type you find at Statistics of the first 18.000 Signatees.
Recently, the executive Director of JISC, David Prosser gave a podcast interview (4th Feb. 2008), on the background and his opinion that Open Access made it at last.
Source: P.Suber, Open Access News 4th Feb.2008