Interesting. I'd heard the term before, but hadn't seen any pics, so I wasn't sure that this was an example of it. I'd also heard that DVD rot was a "myth." (see this article: http://www.techtalkradio.com/features/dvdrot.htm -- which says, for instance, that "... there might be some oxidation on...
http://filmistruth.com/images/dvd.jpg (Click the link to see the disc in question.) I own a video store and I've had a number of Kino discs change color like this. They also stop working, either freezing in the middle or not loading at all. Kino says they've had no reports of anything...