Just read that a few weeks after Yahoo Images added the creative commons search filter, Googles Images did the same. Also, the option is not in the user interface so the filter has to be set by adding a parameter to the URL. The first question to be asked is why has Google not announced this? And why have they not made the new functionality part of the user interface? Those are questions for Google. The question I have for the Forum is how much of an impact will this have on your SEO efforts?