And here is one more from the new Retina MacBook - apple.com
I'm not sure why this keeps popping up in the news, but these have been here since Lion. They were even in the same folder I believe.
These have actually been in OS X since Lion, always in the same location:) I've been using them as my screen savers for a while.
Great find! some of these hidden ones are brilliant!
brilliant wallpapers, great find!
I've actually seen a lot of these on my Apple TV. Probably some stock images left from use in their other software.
Does anybody know why Apple did this?
They're actually used in the built-in photo screensavers. For whatever reason, not all (but some) were included as wallpapers.