Tonight Google’s Matt Cutts announced (via this tweet embedded here) that Google Image search now allows for image filtering based on license.
— Matt Cutts (@mattcutts) January 14, 2014
Sure enough, when I search for photos, there’s now an option to filter based on usage. The terms used correspond with several Creative Commons license variants although the exact terms are modified (ostensibly to be more easily understood… you won’t find talk of derivatives, but rather of modification).
One question without an official answer at this point is where the licensing information is coming from (I replied to Cutts’ tweet but haven’t received a response). I did a bit of poking around at known search results including some of my own images. I’m seeing Flickr photos (with Creative Commons licensing info on the Flickr page) being reflected as such in the Google Image Search results. Indeed I’m seeing that an overwhelming majority of the highest-ranking search results are coming from Flickr and Wikipedia. That said, I’m also seeing other images appear, and as I go to the source website for those photos each site clearly shows the Creative Commons license using the recommended markup. This appears to be a case of metadata markup working correctly!
I don’t see any downsides for photographers… those who wish to retain all of their rights are able to do so, while those publishing under Creative Commons licenses gain another venue for exposure.
(and yes, I’m aware that apparently Bing has allowed for such filtering for some time, but Google’s the king of search so that’s why this is a big deal)