I’ve encountered a couple of the more ‘with it’ librarians mentioning it while running the kiddies through “and this is how to do research on the internet without being a moron, committing plagiarism, or displeasing the copy cops”(I was immensely relieved that ‘copyright infringement’ and ‘plagiarism’ were not conflated; since this happens far too often despite the two concepts being largely orthogonal).
Aside from that, though, I see CC-attributions for images used in some blog posts and such; and on some images on Flickr and various other assorted places.
I suppose the real question is what you mean by ‘working’. So far as I know, the CC licenses aren’t considered to be horribly legally tenuous; and are pretty easy to use if you fall within their use cases(and arguably more appropriate than the software-focused licenses for general purpose stuff); but I don’t get the impression that they have made non-wonks any more interested in the grinding hellscape of ‘rights clearance’ than they ever were; which isn’t much.
If I had to identify one area where CC might be said to be ‘not working’ as opposed to simply ‘not setting the world on fire because it deals with a somewhat esoteric issue that normal humans have traditionally just handled by ignoring’; it would probably be the fact(not really CC’s fault; but, in absence of some litigious entity standing up for CC, not something it can protect you from) that large swaths of the web(eg. Youtube and ‘ContentID’ are, de facto not actually operated under US or other copyright law; but under a rather capricious algorithm bolstered by often-fraudulent DMCA notices; and if ‘ContentID’ thinks that your CC background music sounds too much like some copyright troll; Joe Public doesn’t have too much recourse; and that in other areas (coughGetty Imagescough) there seems to be an embedded assumption that ‘real rightsholders’ are big companies that somebody has heard of; so copyrights of theoretically equal legal weight are often treated as a bit of a joke, even with a formalized CC or other license; compared to ‘real’ copyrighted material by respectable professionals.
The same thing happens to some extent with the GPL: it would be considered somewhere between ‘gutsy’ and ‘suicidal’ for a major consumer electronics brand to ship a few million units running pirated copies of a proprietary software package; but it is almost certainly more the exception than the rule for stuff with GPL software based firmware to ship with something between ‘inadequate’ and ‘utterly nonexistent’ license compliance; and for people to act faintly outraged on the very rare occasions that someone has the temerity to demand compliance.
That said, CC seems to mostly work as advertised; and I can’t blame it too much for the (deeply unjust; but true more or less across the board) fact that if you have ‘respectability’ and enough resources to litigate, your rights are a lot less theoretical than those of the little people.