The most important development in the way we interact on the web will come when a system of micropayments is in place.  The big difficulties are coordination problems and security.  The strongest incentive to build and control a massive social network is that it will enable Facebook to host a micropayments economy within its closed environment, solving both the coordination problem and a big part of the security problem.

Here’s the future of Facebook.  You will subscribe to your friends.  A subscription costs you a flow of micropayments.  Your friends will include the likes of Tyler Cowen, The Wall Street Journal, gmail, Jay-Z, Harry Potter and the Deathly Hallows, etc.

Remember that the next time you hear somebody say that there is no way to monetize Facebook or Twitter.