Lawrence Lessig quantifies how well Creative Commons is doing:
Creative Commons launched the licensing project in December 2002. Within a year, there were more than 1,000,000 link-backs to our licenses (meaning at least a million places on the web where people were linking to our licenses, and presumptively licensing content under those licenses). Within two years, that number was 12,000,000. At the end of our last fundraising campaign, it had grown to about 45,000,000 link-backs to our licenses. That was December, 2005. In the first six months of 2006, that number grew by almost 100,000,000 licenses. In June, we reported about 140,000,000 link-backs to our licenses.
Because I'd like to see the public domain defended against entertainment corporations that want to extend their copyrights forever, I thought the 2003 Supreme Court decision Eldred v. Ashcroft was a terrible milestone for creative work in the U.S. Companies like Disney, after making millions adapting works like Cinderella and Snow White from the public domain, are lobbying to deny that right to future creators.
But as Creative Commons grows, I'm beginning to think we're better off after Eldred because it provided such strong impetus to create a new commons for creative work.