Andrews' book starts out focusing on Facebook, but then goes beyond that topic to the broader issue of firms using the Internet to research customers and sell the information to advertisers, potential employers, etc., and the sometimes negative consequences of their doing so. The material is good and eye-opening, but much of it is overly legalistic (eg. Constitutional and court case references) for my taste.
Facebook has 750 million members, and its founder and CEO, Mark Zuckerberg, has been pitching it as a means of increasing public participation in the political process. Already some have used it to incite and facilitate street protests. Other more nefarious uses include dessiminating terrorist training materials, finding potential burglary targets out on vacation, and sometimes taking personal photos and information out of context. The Department of Homeland Security now monitors it for some 350 terms, per a 1/11 listing. Member privacy has been a major and recurring concern throughout Facebook's lifetime.
Facebook earned $1.9 billion in advertising revenue in 2010, and another 4200 million from revenue-sharing agreements with applications that run on the site (eg. games). Its 2010 Internet ad revenues exceeded those of newspapers by 2010 - 63% of advertising agencies report targeted ads (per online behavior) have increased their revenues. Facebook, however, makes up only 14.6% of the behavioral advertising market.
Cookies, Flash cookies, and zombie cookies collect user information and sell it to others; similarly, search engine logs help to improve searches and also target their (eg. Google) advertising results. Some companies/sites allow users to opt out of being tracked; however, if you don't know who they are, that's not going to happen. Further, many sites don't function properly unless the user accepts cookies, some opt-outs don't work as promised, and others are only temporary.
The federal Computer Fraud and Abuse Act makes it illegal to intentionally access a protected computer without authorization; transmitting and obtaining information from such sources are also illegal. However, an actionable violation must cause at least $5,000 in damages, which the author asserts is usually difficult to prove. Other laws are even less useful because they only require approval of the snooping etc. from the site doing it.
Author Lori Andrews is a law professor, hence the legal emphasis throughout the bulk of the book. Her going back to concerns about paparazzi-type actions by early Kodak camera users was one of the more interesting legal references.