Leveraging social network sites is high on the list of priorities for a lot of businesses that are eager to find more effective ways to reach, learn about, and engage customers in new product development (NPD). However, the rapidly changing landscape of social network sites can be difficult to navigate successfully and doubts remain about whether and how they can be used to good effect. In fact, empirical research confirming a positive relationship between the use of social network sites in NPD and business performance is scarce. This paper reports on research examining the use of social network sites for three purposes, namely for market research guiding the development of new products, for getting customers to collaborate in the NPD process, and for new product launch. The results of this research suggest that the benefits expected from using social network sites in NPD are largely not being realized by businesses. Using social network sites to conduct market research leading into the NPD process was not found to contribute to business performance, and in fact was found to have negative relationships with both profitability and market growth. Using social network sites to get customers to collaborate in the NPD process was found to be positively related with innovativeness but not with market growth or profitability. Finally, using social network sites for new product launch was where the most positive indications were seen, since this was found to be positively related with innovativeness, market growth, and profitability. Thus, it appears that while businesses may get good results from using social network sites for product launch, they still have a learning curve to traverse before they can successfully use them for market research or customer collaboration in NPD. While there is currently a great deal of enthusiasm - even hype - about the potential opportunities of using social network sites for NPD, this research suggests that businesses should move carefully and recognize that just jumping on the social network bandwagon will not insure success.