Ramon Gulikers shared a photo with me on Twitter of Google testing displaying gray and/or green URLs in the snippets. Some are gray and some are green. Ramon said this is not based on what URL he has visited or clicked on in the past, but something else and he is not sure.
Truth is, I have not seen this from Google before. Here is a screen shot he shared:
Has anyone seen Google do this before?
Forum discussion at Twitter.