The traditional sense in going to a webstie is you load it, and click on links - It's just that simple. What if this was a little more complex, but still easy?
Imagine a web page that could be organised in any manner according to the person behind the browser. No specific edits, no specific alignments, no specific anything. One could add pictures, video, music, and share these edits with their friends. More-so these edits would automatically be visible to anyone who was "following." Is this confusing? I hope not. Just think of it as a Status / Twitter on steroids. A way for people to manipulate web pages as they see fit.
I would assume that every web page would look normal - But would then be manipulated by each visitor (if they wanted to). Of course these edits would be locked to said user.
If you've ever used Google Docs, or Etherpad, you should understand exactly where I'm going with this. Multiple people could edit a page, and have a deeper interaction with the website/online service. Eh? Sure, a comments box, Social buttons, and so on aren't bad. (But) What if these changes stuck, and could be de/centralised as needed. Similar to the diaspora model, 'cept a little more intense.
Though I could be jumping the line here. Maybe the web isn't ready for a such thing, yet. Who knows.