It's a "collection of visualization projects built on Wikipedia data, curated by Hatnote."
An interesting study, in my opinion, with initial thoughts (around 2004) on how can we study the movement is: Wikipedia as Participatory Journalism: Reliable Sources? Metrics for evaluating collaborative media as a news resource - http://www.ufrgs.br/limc/participativo/pdf/wikipedia.pdf
That's is what I remember by now, I am also interested on propose/test such metrics (mostly quantitative ones) and study it further.