Months after it was first published I am still digesting the content of the essays in Edge.org's question of 2007. If there is a single document I would advise everyone to read on the Internet it would be this.
One of Jaron Lanier's comments concerns the ability of the human mind to learn to control bodies that are very different from the ones we currently wear. This idea is called homuncular flexibility. From Edge.org:
Some of the most interesting data from VR research thus far involve Homuncular Flexibility. It turns out that the human brain can learn to control radically different bodies with remarkable ease. That means that people might eventually learn to spontaneously change what's going on in a virtual world by becoming parts of it.
This may result in scenarios similar to those described in Greg Bear's sublime Eon, in which posthumans communicate using an elaborate set of VR "picts" to supplement traditional, linear speech.
More information on Jaron Lanier's ideas of homuncular flexibility can be found here in last years Edge.org question (What's your Dangerous Idea?).