Here is an excellent presentation by Mike Liebhold at this 2008 Metaverse U conference that summarises some of the upcoming and existing technology that I think will have significant impact on the way we blend virtual worlds with the real world.
Mike Liebhold provides a glimpse into a near future changed profoundly by augmented reality. This disruptive technology gets us thinking about the impact and challenges we face of the blending of 2D/3D geodata and virtual worlds. Psychologically speaking, dividing the perceived space we navigate across virtual and real worlds may have considerable drain on our ability to differentiate these domains. At some not so distant time in the future will we be able to separate one from the other? How will we come to relate to synthetic lifeforms that navigate this space and will we see digital migration to higher bandwidth virtual/real locations? Mike's talk ponders the challenge of these complex future digital/real environments.