The chromecast screensaver is the background on the TV in my Airbnb. Multiple guests have told me how much that screensaver makes them feel at home when they travel, and makes the world a little less strange.
I'm unsure which screensaver photos we're talking about--but if it's the nature photography (and others that you can choose from) which play when nothing is casting to Chromecast, then I have at least one instance where I have seen photos by a person I know is a photographer and not a Google employee (Trey Ratcliff).
Can't find a source for that, but have many times corroborated that through a Google search. Peter Norvig is one of them.