Today I use raindrop.io for bookmarking, but something like that with a somewhat more social aspect existed much earlier. I had accounts at Mister-Wong and del.icio.us around 2007. Both don’t exist anymore. Mister-Wong is now a weird news site and del.icio.us is empty at the moment but owned by the developer of Pinboard, so at least someone who knows about bookmarking. But it’s funny. What was cool back then somehow went down over the years, only to rise again like Phoenix from the ashes. So in the end like the bell-bottoms or dungarees.
Closing words: While Raindrop.io is not a social bookmarking tool, you can share bookmarks. Much like with Pinboard.