Discovery has become the one thing that our social networking overlords do and focus on. But we learned about new things before them just by talking with our peers. I think the IndieWeb's concept of a Social Reader[1] can do a great job of filling this need. If you like or comment on something in your feed-reader, it becomes a post on your outgoing feed that people can see. This lets any individual or site act as a source for curated content.

[1]: https://indieweb.org/social_reader