The phenomenology of B decays into two vector mesons offers the possibility of measuring many observables related with the angular distribution of the final outgoing particles. Here we study in particular decays into Phi K* states, which can be used to disentangle annihilation contributions to the amplitude and to look for effects of physics beyond the Standard Model through CP violating observables. We show that the analysis also serves as a test of the consistency of the factorization approach.