Hmmm, this sounds like a Ben Bova novel. :) I like it.
http://ca.news.yahoo.com/google-execs-director-cameron-space-venture-005212432--sector.html (http://ca.news.yahoo.com/google-execs-director-cameron-space-venture-005212432--sector.html)
I heard about this on the 'Mysterious Universe' podcast. They were saying that the energy needed to leave the Earth's atmosphere has always previously made the possibility of mining asteroids an impossibilty.
But now imagining super giant massive deep space mining ships. And being a fan of Red Dwarf, this makes me happy :)