Vincenzo, in fact, the BIG key point, you are talking about, is URI: the Unique location of a resource.
For social media, the keypoint is semantic web. The way for a computer to understand the human language in order to dynamically create the link between each object, person, concept.

A hard work and as you said actually each social service has its own way to store “things” and doesn’t want to interact with others.

Just remember how simple the Web was at its beginning: just typesetting and hyperlinks, not even javascript!!

But the real enabling force of the web was exactly that simple thing called “hyperlink” that changed the world. The concept was simple, powerful and easy to implement (for end users who became publishers). It turned the world upside down.

We still don’t know if there will be something analogous to that “simple thing” for social media. Maybe there something yet to come… Before the Web there were other means to share information on the Internet (i.e. FTP, Gopher, Usenet newsgroups) but none of them had the enabling power of the Web. The idea was the same: sharing information on the Internet. But the modality was dramatically different!

For Social Media we might be at this early stage. The idea is: collaboration on the Internet. But there’s still no breakthrough modality. When Web started, the adoption was massive and fast. All other technologies were basically abandoned (or used for niche applications or by nostalgic users).

For Social Media we cannot observe the same behavior: MySpace users don’t switch to Facebook or Twitter massively. People collaborate with different technologies and there is no a unique Internet technology that replaces all these tools and leverages collaboration into massive adoption as it was the case for Web in information sharing.

So, there is room for innovation. I really wish you that you could come up with a new (simple) idea and revolutionize the world as it happened with the Web!

All the best!