From my co-author, David Teten:

I just received the email below from Amazon:

You have been selected to answer a quick survey regarding online networking, online services that enable business professionals to store and generate new contacts with other business professionals online. You may or may not currently be an active user of an online networking service, however, we would be interested in hearing your candid feedback.

The survey should take no longer than ten (10) minutes of your time. After you answer the last question of the survey, you will be signed up to receive your free $10 Amazon shopping credit.

Translation: Amazon already has a powerful online network in their community of reviewers, their wish lists, and the huge amount of behavioral data that they have collected. Now, they are trying to figure out how to monetize this more effectively, and are looking at the social network software firms as models. I took the survey, and it looks like they are comparing the major social network services and determining the advantages and disadvantages of each.