GNU social is a continuation of the StatusNet project. It is social communication software for both public and private communications. It is widely supported and has a large userbase. It is already used by the Free Software Foundation, and Richard Stallman himself.
The history of GNU social
GNU social was started in 2010 as a spin-off from the GNU FM project that was created to power music communities such as Libre.fm. In 2013, Evan Prodromou continued to develop social software for the web as Pump.io, and kindly donated all of his work to the Free Software Foundation, so we merged the existing project with StatusNet and another project called FreeSocial. And here we are. More Info »
Thanks to Bytemark, GNU social has a new home in the UK, with resources to open a series of public GNU social servers for new users, including private servers dedicated to GNU social development.