Abstract: 
After a review of the muon g2 status, we analyze the
possibility that the present discrepancy between experiment and the
Standard Model (SM) prediction may be due to hypothetical errors in
the determination of the hadronic leadingorder contribution to the
latter. In particular, we show how an increase of the hadroproduction
cross section in lowenergy e^{+}e^{} collisions could bridge the muon
g2 discrepancy, leading however to a decrease on the electroweak
upper bound on M_{H}, the SM Higgs boson mass. That bound is currently
M_{H}<˜150GeV (95%CL) based on the preliminary top quark mass
M_{t}=172.6(1.4)GeV and the recent determination Δ
α_{had}^{(5)}(M_{Z}) = 0.02768(22), while the directsearch lower
bound is M_{H} > 114.4GeV (95%CL). By means of a detailed analysis we
conclude that this solution of the muon g2 discrepancy is unlikely in
view of current experimental error estimates. However, if this turns
out to be the solution, the 95%CL upper bound on M_{H} is reduced to
about 130GeV which, in conjunction with the experimental lower bound,
leaves a narrow window for the mass of this fundamental particle.
