Most of new product diffusion models assume (1) WOM has a positive impact on new product adoption; (2) WOM is spread only by the adopters having usage experiences in the product. We relax these assumptions by incorporating a negative WOM into the model following  and, moreover, by allowing consumers to spread WOM even without usage experiences. These extensions are more plausible to deal with more novel products that could be very attractive but is highly uncertain in terms of post-purchase satisfaction. In addition, our model also incorporates more complex network structures into links between consumers. This setting might enrich our understanding of WOM propagation among consumers by examining the role of hub consumers, who are linked with a large number of peers, which is one of the controversial issues in practices of WOM marketing  From a managerial viewpoint, we finally discuss in what conditions, which consumers should be selected as a target segment.