  We discuss a novel electromagnetic penguin contribution to the transverse
helicity amplitudes in B decays to two vector mesons, which is enhanced by two
powers of mB/Lambda relative to the standard penguin amplitudes. This leads to
unique polarization signatures in penguin-dominated decay modes such as B-->rho
K* similar to polarization effects in the radiative decay B-->K*gamma, and
offers new opportunities to probe the magnitude and chirality of
flavour-changing neutral current couplings to photons.
