The Declaration of Interdependence at headmap is definitely worth reading. For headmap, the Internet has been misunderstood. Most view it as an economic engine which basically increases productivity, and early "marketplaces" on the web actually replicated marketplaces in the physical world. This was indeed my own view when I started working on "knowledge marktplaces" back in 2000.
It's an economy engine, rather than an economic engine. It hosts markets. Link economies, file sharing economies and one particular world wide garage sale. It can bring a whole complex market infrastructure to any given physical transaction. Rather than looking for cash replacements, for some mythical ecash, consider the internet itself as the exchange facilitating mechanism.
For headmap, the trend is towards less centralized eBay-type markets and more "decentralized, structured, logically interconnected, people centered and increasingly location aware" systems announced by peer-to-peer platforms like Gnutella or Napster. Hence, cash is no longer the sole exchange mechanism in a more and more interdependent world.
I basically agree. A lot of human interactions that used to be handled in a transactional mode for lack of a better way can now be handled in a community mode as it happens for example within a family. Paradoxically, the web makes you more visible, and does a much better job at managing your reputation than the physical world, because the web never forgets. I am always surprised when I type my name on Google to realize that what is out there really shows who I am and what my thoughts are, at least in the professional arena (I have the chance of having a unique name)
But headmap seems to ignore that there is a dark side to that. In the physical world, you can be relatively anonymous. If something bad happens to you, you can always move to another place and start another life. On the web, there is no such thing. Either you are present in cyberspace, and your reputation is apparent, or you are not there, and you are an alien or a suspect. I tremble when I imagine that all these data concerning me can be manipulated. They can, and they have.