From Social Patterns
Ongoing sharing may also be described as passive sharing. It refers to any process through which participants may initially opt in to enable their activities to be tracked and posted as updates to Activity Streams.
Whenever I log in to Flickr or Vimeo or Slideshare one of the things I see right away are recent uploads from my contacts.
Different from directly sharing content with individuals or even actively sharing it with different sized publics, ongoing sharing is a less conscious but more pervasive form of sharing, discussed at length in Updates.
It's a good idea to occasionally remind people that they're sharing information passively in an ongoing way, to preserve them from the inadvertent indiscretions that can follow from forgetting who's watching you.