Have you considered refreshing this 'map' periodically and/or adding this to either the Clojure website or wiki? I think that'd be a nice way to help people stay abreast of useful up-and-comers.
The vast majority of Clojure projects all seem to live on github. So, perhaps one way of picking out important projects with one/few contributors could be by looking at projects with high numbers of forks or watchers?