Do research on the Web to identify examples of a social network allowing a large national retailer to mine its data to learn more about the social network members and to develop targeted direct...

Do research on the Web to identify examples of a social network allowing a large national retailer to mine its data to learn more about the social network members and to develop targeted direct mailings and emails promoting its products. What are the pros and cons of sharing such data? How do social network members feel when they learn that their data is being shared? In your opinion, under what conditions is this a legitimate use of social network member data?