Marketers have traditionally used research methods such as focus groups, observation, trend analysis, and competitive research to help develop and gauge customer response to new products.

Today, social media is also helping companies understand consumer preferences and develop new products. Have a look at how Wal-Mart, Frito-Lay, Samuel Adams and Kohls are using Facebook and Twitter and let's try to answer the following questions:

For these companies, how is social media useful for marketing research? What other companies and products might benefit from this approach? What are the pros and cons of using social media for market research?