Mailing the story:

The Sabayon Community Repositories infrastructure will build repositories for the community, and it is managed by the community itself. There is a main Community repository while there is room to add other repositories, "slots", that SCR Developers are free to use. More on how it works will come later. Currently we are in alpha state, but we are having great results, some packages are already available to the public. The goal here is to have a system like AUR for Arch and PPA for Ubuntu where Sabayon Community Developers (which are community members first) maintain multiple repositories or packages of the Community repository.