Wikia, the independent commercial wiki site founded by Wikipedia’s Jimmy Wales and Angela Beesley, is releasing components of its very nice social networking toolset under the GNU General Public License 2.0.
The ability to set up an Open Source social network is now available to anyone who can put a Mediawiki install on their servers. Look out Ning and other proprietary social networking platforms!
You can see Wikia’s social networking features live at the popular sports community ArmchairGM (acquired by Wikia for $2m) and the newly re-launched Halopedia, a community for Halo fans.
ArmchairGM in particular has been a big social networking innovator in the Wiki market and was acquired to help drive the design of the whole Wikia ecosystem. That site is made up of news driven editorial and has a remarkably active community of participants.
Why do social networking on a wiki? On one hand, a wiki is just a web site that’s easy for anyone to edit - see Mahalo for example, another Mediawiki-based community. Beyond that though, social networking features create more points of contact for users with a website and help populate the site with content far beyond what the site’s owners or solitary users editing alone could put in.