It's content discovery without any algorithms involved, and only works well on things that have actual URLs (so no dynamically generated "feeds" and so on).
I've been writing a bit about content discovery sans algorithms and I think there is at least some number of people would be interested in it. Social curation is appealing, though I'm not sure how popular a dedicated site for curated link sharing would be. While things like Reddit, Twitter, etc. are not 1 to 1 replacements, I think it serves a similar purpose for a lot of people.
Reddit, Twitter etc. are quite okay for naturally-ephemeral content but if you want to share a stable/growing bookmarks collection, or even cooperate with others sharing their own, there's nowhere to do it. DMOZ used to work quite well aside from the usual controversies relating to its centralized moderation, and a federated variety of that plus something like delicious/stumbleupon for "tags" and folksonomy would be interesting to experiment with.
(edit: typo)