Update: here is Colbert's take on the issue. He explained to us what was "priceless" for the Bush government. HT: Environmental economics.
Update: Mark Thoma explained what the value of a statistical life means.
"...it is not the “value of a human being” that is in question in this case. Instead, it is people’s own willingness to pay (that is, their own demands) for small risk reductions, and there is no reason why this willingness to pay should be the same for everyone or for all types of risks.
Simply refusing to put an explicit dollar value on mortality risk reductions does not mean that the comparison of the costs of a regulation to its benefits can be avoided. If a regulation is put in place, we can assume that somebody decided that the mortality risk reduction it would achieve was “worth” at least as much as the costs created by the regulation. Governments use explicit values for mortality risk reductions to enhance transparency about how decisions are made.