  We improve the resummation calculations in the ResBos program for the Higgs
boson production via gluon-gluon fusion by including the NNLO Wilson
coefficient functions and G-functions. The improvement leads to increasing the
total cross section predictions of the new ResBos program, dubbed as ResBos2,
for Higgs boson production by about 8% and 6% at the Tevatron and the LHC,
respectively, as compared to the old ResBos program. Furthermore, the improved
predictions are compared with those from the programs HNNLO and HqT2. We find
that they agree well for the total cross sections but differ slightly for the
transverse momentum $Q_T$ distributions. With ResBos2, we present the
distributions of the two variables $a_T$ and $\phi^{*}$, which can have better
experimental resolutions than $Q_T$, for the process of Higgs boson decaying
into a photon pair. Theoretical uncertainties of the ResBos2 predictions are
also discussed.
