The Repository for Community Server is up on svn://sgdotnet.org/CommunityServer
The directory structure is as follows :-
/trunk <---- The main development
/branch <---- Branches made in the development
/tags <---- Releases made
Most of the developers will work on trunk. The maintainers will decide and prepare the Releases under tags. Branch will be test work you want to try out and share with other developers to work on before merging with the trunk.
Cheerios.