GitHub now supports rendering TopoJSON, an extension of GeoJSON that encodes topology and can be up to 80% smaller than its GeoJSON equivalent.
Complex geographic datasets can often be difficult to visualize, especially if points are grouped close together. We now automatically cluster nearby markers, allowing us to better support larger datasets.
- GitHub Blog via @cageyjames
--- original post 6/17/13 ---
An e-mail from the folks at GitHub (though we'd already seen the buzz on Twitter) announces new mapping visualization on that platform. (Not sure what GitHub is? See Directions Magazine coverage.)
TL;DR: commit a .geojson file to a repository, and GitHub will render any points, lines, or polygons as an interactive map, complete with custom markers and tool tips. Plus, we're using MapBox under the hood, so every thing's OSM-backed.
Esri is already working on GeoJSON support http://esri.github.io/#GeoJSON
[This gives the geospatial community] the ability to treat geodata as open source code and collaborate on and track the history of individual datasets...