And I'm going to repeat myself: economics is the science of distributing resources under conditions of scarcity. (There's a hint there -- scarcity.)

If you abolish scarcity -- howsoever you do it -- one of the constraints has broken and you need to look outside the box for a way of treating it. I'm not convinced that classical economics, or Marxist economics, or any other kind of economic theory we have to day, has a hell of a lot to tell us about a post-singularity society or a post-scarcity society.

In fact, I'd go so far as to say that I figure economics is the last big untapped science waiting to be discovered by science fiction ...