Who remembers Jet Blue turning over their passenger data to an Army contractor after 9/11?
"JetBlue Airways acknowledged publicly today that it had provided a Pentagon contractor with information on more than one million of its passengers as part of a program to track down terrorists and other ''high risk'' passengers. That data, which was turned over in violation of the airline's own privacy policies, was then used to identify the passengers' Social Security numbers, financial histories and occupations."
<http://query.nytimes.com/gst/fullpage.html?res=9C02EED7103AF933A1575AC0A9659C8B63>
So a routine handing over of data by Facebook would be pretty disturbing, but past pratice would suggest that nothing is really safe when there's a "security need."
As for marketing information, Danah Boyd makes an insightful observation about young Web 2.0 users, who learn that loss of privacy begins at home:
"Teens are growing up in a constant state of surveillance because parents, teachers, school administrators and others who hold direct power over youth are surveilling them. Governments and corporations are beyond their consideration because the people who directly affect their lives have created a more encompassing panopticon than any external structure could ever do. The personal panopticon they live in (managed by people they know and see daily) is far more menacing, far more direct, far more traumatic. As a result, youth are pretty blase about their privacy in relation to government and corporate. Cuz realistically, in comparison to parents/teachers, what can they do? Privacy folks should be worried about where privacy is going with the next generation, but the erosion is happening on the home front, not on the corporate/governmental level. Unless we figure out how to give youth privacy in their personal lives, they are not going to expect privacy in their public lives."
<http://www.zephoria.org/thoughts/archives/2006/05/20/erosion_of_yout.html>
I have to credit Geert Lovink, and his roughly edited but extremely useful _Zero Comments_ (Routledge, 2008) for this particular Danah Boyd quote.
Best, Charles