As people become increasingly comfortable posting their lives online via social networks like Facebook or through microblogs like Twitter, some companies have begun to build Web dossiers of consumers. They do this by mining the social Web on Facebook, Twitter, blogs, and online forums. Then they sell it to other companies. And here is the deal . . . most consumers have no idea that this is being done.

While the use of customer data has been around for a few years (especially through companies like Amazon who use algorithms based on customer searches and purchases to make product recommendations), there are some privacy advocates who feel that mining and using data from the social Web crosses ethical lines. For their part, the companies that aggregate this information say that they are using this information to detect behavioral patterns in order for companies to provide better products and customer service.

1. Do think that this practice violates privacy, or is it acceptable since it uses information that a person has posted voluntarily?

2. What are some promising ways that companies can use this data?

3. What are some questionable ways that companies can use this data?