We mentioned the project two times earlier this year, and now GeoNode 1.0 has just been released.
From their about page: "GeoNode is an open source platform that facilitates the creation, sharing, and collaborative use of geospatial data. The project aims to surpass existing spatial data infrastructure solutions by integrating robust social and cartographic tools.
At its core, the GeoNode is based on open source components GeoServer, GeoNetwork, Django, and GeoExt that provide a platform for sophisticated web browser spatial visualization and analysis. Atop this stack, the project has built a map composer and viewer, tools for analysis, and reporting tools.
To promote collaboration, the GeoNode is designed on Web 2.0 principles [...]"