  If the lightest dark matter neutralino has a sufficiently large Higgsino
component, its spin-independent and spin-dependent cross sections on nucleons
can be sizable enough to be detected soon in direct and indirect surveys. We
outline in this paper some characteristic features expected of mixed
bino-Higgsino dark matter. If the observed relic density is saturated by the
bino-Higgsino dark matter, it fixes the amount of allowable bino-Higgsino
mixing and provides predictions for other observables which can be tested at
the Large Hadron Collider (LHC). We study the correlation between the cross
sections and the branching ratio of B_s -> mu^+ mu^-. For a mixed bino-Higgsino
dark matter, the mass differences of the neutralinos can be less than M_Z. This
will cause an excess of lepton pairs, above the Standard Model predictions,
from the decays of the two heavier neutralinos. We discuss implications of the
dilepton invariant mass distribution, and outline a way to extract the
neutralino parameters for testing gaugino mass unification and deducing the
relic density from an interplay of astrophysical detection and LHC
measurements.
