This task is for the Hackathon in Lyon. Nod proper project.
Thanks to many great contributors, we are proud to present [[ https://www.mediawiki.org/wiki/Extension:Graph/Demo | the Graphs ]]... because wiki pages with SVG and PNG images is so last century. [[ https://www.mediawiki.org/wiki/Extension:Graph | Graph extension ]] allows content authors to insert a data-defined graph or a map in a wiki page. Graph is described using [[ http://trifacta.github.io/vega/ | Vega visualization grammar ]] ( [[ http://trifacta.github.io/vega/editor/ | demo ]]), and allows very complex data transformations, filtering, and soon even animation & interactivity. Combine that with the power of wiki template parameters and Lua scripting, and the results could be stellar. Up to you really. Vega+d3 gives us a huge list of charting options and maps with numerous projections and ability to highlight individual regions. Lastly, graphs could be rendered either in a browser (more interactivity), or on the server (faster load). Demo will be served.
Special thanks goes to milimetric, krinkle, Brion, and gwicke, without whose help this project would have been a lot harder, and to Vega and other open source teams who build such great libraries.