The legendary architect Christopher Alexander has a theory on how life flourishes: at its core is this idea that the world consists of overlapping "centers" – basically places where living things gather. Centers can overlap, so on Facebook your feed and your profile are each centers. By connecting centers, you encourage movement between them and a newer, greater center exists.
I feel that Facebook and Twitter are excellent at encouraging this movement between centers of data. But they're not good at making that data matter. MySpace and Geocities were awful at communication (remember MySpace bulletins?), but they were always about creating something unique for yourself, not about connecting you to anybody else.
Is there a way to do both at once? I'm not sure, but this is something I've been thinking about for a few years now. In high school I did some work for http://zoints.com, which was trying to create a network of connected forums to allow for both personal expression and information density, but their tool was way too cerebral for anybody else to catch on. The closest I think I've seen any site come to this is Tumblr, because it both allows for uniquely designed blogs and a central aggregator, but Tumblr is so bad at conversation that it makes holding lengthy conversations ugly and frustrating.
The theoretical solution to this would be to let users define their own centers: give them controls for looking at information in a unique way of their choosing. In a sense, this solution is the Internet, and things like email and RSS are how we connect disparate online entities, but those are very crude tools. The subtler interactions you allow for, the more you'll let people express themselves without getting in each others' ways – but it's hard to define just what these interactions ought to be.
Looking back I'd say the pinnacle (for me) was Facebook's Graffiti Wall app, back when apps were just starting to be a thing. People interacting through pictures and illustrations lent to much more creative back-and-forth than text ever did. But that wasn't ideal either. I love capturing and organizing information, but I agree with you that something's been lost. Reclaiming it without sacrificing the new will be an enormous challenge.
http://www.ribbonfarm.com/2010/10/27/warrens-plazas-and-the-...
Who are the winners, the high-value brands? Apple and Facebook, who maintained control. Apple and Facebook can't stop their users from doing tacky things with their products (not yet, thank God) but they do make sure the carefully designed brand context is always visible and easily distinguishable from the user-generated content inside. Who are the losers, the low-value brands? MySpace and other companies who didn't maintain a strict distinction between their product and what users did with it.
http://1.bp.blogspot.com/-CukACmTPP8Q/TxxdPO_B8HI/AAAAAAAADd...
and, using our existing UI tools, made it look like this:
http://www.ilenesmachine.com/eworld/images_eworld/eworldone....
We had no idea that was possible.
Lesson: You do want your users customizing the interface.. but only the right users.
MySpace tapped into this also , allowing people to change their page background, have autoplaying music etc.
The facebook/Twitter came along and spoiled it by prioritizing usability. Now basically everyone has an online presence that looks identical to the point of being sterile. Hell even 90% of wordpress sites look exactly the same.