This is a preview of a work-in-progress visualization script that uses the MediaWiki api to visualize users and page edits. This is an example on rit's Ritpedia.
The visualization is currently using ubigraph to draw the visualization and a custom python program to generate the data for the graph.
Pages are represented by blue squares and users who edit them are represented by the red diamonds. As pages are edited by a user, they are added to the graph. It also creates nodes for any page that the edited paged linked to.
The second mode disables the users and just shows the pages and how they are linked. Note that this is still a very new wiki.
This visualization can run in almost real-time (pulls updates at a configurable interval).
MediaWiki Visualization Preview