  We compare the WW and pomeron-pomeron fusion mechanisms for the
double-diffractive production of a Higgs boson. We determine the suppression of
the 'rapidity gap' pomeron-pomeron fusion events due to QCD radiative effects.
In particular we use leading log techniques to estimate the cross sections for
both exclusive and inclusive double-diffractive Higgs production at LHC
energies. The same approach can be applied to the double-diffractive central
production of large E_T dijets. These two processes provide one of the most
justified applications of various aspects of leading logarithm QCD techniques.
