Social bookmarking services that add metadata to web content are reminiscent of the web 2.0 vibe. In terms of adding metadata, I'd say the Semantic Web more than just web 2.0.
I'm tempted to mention the possibility of it becoming a metadata index database for web content, but data persistence and a universal index would be overkill for a relay server design, and those things have been talked about extensively with other spaces like SOLID, IPFS, so I'll refrain. This would be something that 10-100 phase people will resolve somehow with the business!
