When Flickr first announced "interestingness" I declared "let the gaming begin". There's at least one Flickr group, with a decent burst of activity, devoted to cataloging interesting photos along with occasional debates on how the ranking algorithm works. Not to mention a few long, interesting, discussion threads, regarding the relative merits of interestingness and discovering good new images.
The more active and/or older members of Flickr seem relatively hostile to interestingness which seems to have a heavy component of popularity baked into it. The more experienced folks seem to want tools for navigating smaller social spheres, as exemplified by this conversation. I'm often struck by how popularity is valuable because it's a cheap, easy indicator, built out of lots of evaluations, of certain qualities. However, once you get out past those low hanging fruit, or start measuring different qualities, the useful indicators are hard to find.
As social media environments become massively richer in, and expose more, metadata it'll be interesting to see how tools for semionauts are designed and constructed. Marcos Weskamp's FlickrGraph is about the closest thing I've seen and that only let's you explore the underlying social network, leaving out photos, the central media of Flickr!!