I have no inside info on this one, but it sounds like a positive development. PetaPixel writes,
Google Images is continuing to make changes that benefit photographers. The image search engine is testing a new “Licensable” badge that aims to help photographers sell their photos through search results. […]
By specifying licensing information for the photos on your website, Google will automatically add a new “Licensable” badge to the photo’s thumbnail whenever it shows up in Google Images results. The badge tells viewers that license information is available for the photo.
Check out this post from PhotoShelter’s founder, who seems enthusiastic, for many details.