One more point:
The biggest problem most people have with extropianism is its voluntary nature. The idea of a society based not on coercion and force but on cooperation is anathema. A while back I wrote:
: It's ironic. We tell people that 30 years from now everyone will turn
: into an immortal superman, and they say ho hum. But if you suggest
: that somebody ought to be able to work for less than the minimum wage,
: all hell breaks loose.
Hal