Flickr's "Interestingness" formula?

beans & franks, french style, originally uploaded by sindlinger.

Not sure how exactly this formula works. I believe comments and favorites play a significant factor. The number of views also is likely to be important, perhaps, as an indicator of how interesting something is. But I am really not clear on how the variables are weighted. I have ~3,000 photos uploaded to Flickr. All kinds of subjects, locations and compositions. But according to Flickr, this photo above is --- and has been for a while --- the 'most interesting' photo of them all. 'beans & franks, french style' is the best work I've submitted, apparently.