I wonder two things:
First, why just photos? Couldn’t interestingess become valuable in an overall search algorithim?
But second, in an interesting comment discussion under my post yesterday on interestingness, KirkH asks whether interestingness requires that the content judged be hosted on one site. That’s a good question, for interestingness appears to be about both vectors of interest and also about relationships and I’m not sure whether or how the data to feed that algorithim can be done across a distributed network.