Is this a known issue? Take a look at "what links here" for this image: http://en.wikipedia.org/wiki/Image:Chambord_pano.jpg
It claims to be "linked to" by 50 or more pages - most of them user pages that have {{POTD}} on them. However, that template no longer refers to the image.
As a test, I updated one of the user pages (just adding a space) and the set of "what links here" updated, removing that entry.
Steve