  We show -- by explicit computation of first-order corrections -- that the QCD
factorization approach previously applied to hadronic two-body decays and to
form factor ratios also allows us to compute non-factorizable corrections to
exclusive, radiative B meson decays in the heavy quark mass limit. This removes
a major part of the theoretical uncertainty in the region of small invariant
mass of the photon. We discuss in particular the decays B\to K^* \gamma and
B\to K^* l^+l^- and complete the calculation of corrections to the
forward-backward asymmetry zero. The new correction shifts the asymmetry zero
by 30%, but the result confirms our previous conclusion that the asymmetry zero
provides a clean phenomenological determination of the Wilson coefficient C_9.
