New app / social network by Onionlab to create, organize and share playlists of audio and video content. Designed primarily for music, playlists can be made with content hosted on SoundCloud, Vimeo, and YouTube:
Playmoss, the tool that lets you organise all the music you listen online in YouTube, Soundcloud or Vimeo.
With Playmoss, you can arrange all the tracks you like in playlists and share them with your friends and acquaintances, as well as discover new songs or playlists of those users you have musical affinity with.
The site is currently in beta, but you can sign up with an email address or with a Facebook account.
To get an invitation code, you can message their Facebook page to get one (Playmoss FB page link here)
You can sign up to Playmoss here