Two new poly social networks have been launched recently!
The first is Beyond Two, a poly dating and friendship site. Launched in September 2013, it uses a dating/Facebook format and is family-friendly. There are configurations on the site for every possible scenario. Membership growth has been steady and strong, with members all over the world, but predominantly in the U.S.
The second is Polyamory Network, a social network for anyone with an interest in polyamory. It is very new, having launched mid-April, but the owner has contacted large interest groups in hopes of spreading the word. All content can only be accessed by members.
Both sites are completely free.