I am suprised nobody mentioned it already, but the Google Wave Protocol [0] was exactly about bringing some of these properties back to the Web: easily discoverable information, real-time data feeds, decentralization of content, running your own "site", etc.

The author said "we've abandoned [these] core values", and this is precisely why Wave failed: people don't care enough about these values.

[0] http://googlecode.blogspot.com/2009/05/hello-world-meet-goog...