  We introduce a quantification of the question in the title: the logarithmic
sensitivity of the relic neutralino density Omega-hsquared to variations in
input parameters such as the supersymmetric mass scales m_0, m_1/2 and A_0, tan
beta and the top and bottom quark masses. In generic domains of the CMSSM
parameter space with a relic density in the preferred range 0.1 <
Omega-hsquared < 0.3, the sensitivities to all these parameters are moderate,
so an interesting amount of supersymetric dark matter is a natural and robust
prediction. Within these domains, the accuracy in measuring the CMSSM and other
input parameters at the LHC may enable the relic density to be predicted quite
precisely. However, in the coannihilation regions, this might require more
information on the supersymetric spectrum than the LHC is able to provide.
There are also exceptional domains, such as those where direct-channel pole
annihilation dominates, and in the `focus-point' region, where the logarithmic
sensitivity to the input parameters is greatly increased, and it would be more
difficult to predict Omega-hsquared accurately.
