Here's a slight detour into technological futures:
I call augmented reality: "reality +" Anyway, it's coming and my friend Jamais has done the most work/thinking on it that I can find anywhere. Here's a recent slide deck. Video's soon here.
Note, the reason augmented reality (reality +) will be more popular that virtual reality (game worlds, second life, etc.) is due to the need for a common conceptual layer to simplify interconnection. In this case, it's the common geographical reference that everyone shares. Further, it needs to be the real thing: why go to a "fake" Paris when you can go to the real Paris virtually?
(((hilariously, there are government and corporate research groups out there that are going to spend tens of millions of dollars to figure out these simple conclusions over the next couple of years)))
Virtual worlds will therefore always be relegated to fantasy worlds (which will become the great addiction, far beyond drugs, of the 21st Century). Reality + will bring us to an entirely new level of danger and opportunity.