Here are my shots that made it to Explore. It is fascinating to me that the largest value of interestingness comes from the camera you used and not the content you shot. I have a Nikon D40 and a Sigma DP1. I've had 10 photos on Explore thus far out of which 7 were taken with the Sigma DP1. I've taken dozens of others with the Nikon D40 that are of similar content quality or better but don't make it to Explore. I am almost certain that part of the algorithm for Explore has to do with the camera you used (40%) + comments (15%) + faves (15%) + views (20%)... or something like that. All I am saying is that if you have a good eye, it shouldn't matter what camera you used.