What does “Non-Scene” mean?
This means that the release in question is not from “the scene” – it was not released by a genuine scene releaser but by either a one-off user, or other organised group of people. Official scene releases obey the Scene Rules.
Scene releasers distribute their releases via TopSites, not Peer-to-peer or Usenet NewsGroups. Non-scene releasers include individuals like aXXo, and tend to release directly over BitTorrent. In the end, a lot of actual scene releases end up on BitTorrent, thanks to people leaking them onto public sites. The scene members largely object to this behaviour.