Within the very broad scientific debate on the role of heterogeneities in models of innovation diffusion, there seems to exist a delay of marketing science in absorbing the fecund developments that took place, in the field of epidemiology of infectious diseases in very recent times. This paper, which constitutes the basis for a future research project, aims to fill this gap. This is done along three main directions. First, the paper discusses in general terms the role of the concept of heterogeneity in innovation diffusion. Second, it reviews those recent epidemiological results which are of crucial interest for marketing models. Finally, it offers a sample of results which are suggestive of the critical role played by heterogeneities within deterministic models for the diffusion of new products.