@yaxu
Sparks this thought.. In federated wiki, if somebody forks your page you know about it - the flag on your origin page displays a tag <Older/newer> showing where others are at with their usage of your source. This 'neighborhood' feature makes fedwiki an 'awareness engine'.

Doesn't the opensource world have equivalent machinery? Maybe an inventor might create a wiki page for any invention. And others could 'subscribe' by forking the page into their own wiki log of adoptions.