Interesting, in the past I worked on a music discovery tool with a similar interface.

I'm not sure this actually works in the app space though. I think what you're showing is apps similar to a starting point. But do I want more apps that are similar to the apps I already like? Or do I want a new app to do something that I don't already have a solution for? I suspect the latter is more important, possibly with the exception of games.

Nice work on the interface though. I think you could find another use for it. Maybe by showing a people who have app x also have app y may be a better model to go with rather than app similarity.