1) Behavioral Targeting
"Behavioral Targeting," or compiled user-profiles that track online activity have raised privacy concerns because of their tendency to end up in the hand of third party advertisers. There are instances in which this type of information could be used detrimentally against online user.
"Would users about to apply for health insurance want the insurer to know that they had recently been searching for 'symptoms of colon cancer'?"
As the story about NebuAd has shown, there is legitimate public concern strong enough to topple firms that engage in behavioral targeting techniques regardless of the companies intentions.
It's unfortunate, though, that 65% of online marketing firms plan to use behavioral marketing practices despite public opposition and concern. Congressional hearings pertaining to this issue are in line of sight, and indeed, the only way public concern is likely to be addressed.
2) Tracking Technologies
Tracking technologies were first identified on a public level in an article published by Financial Times of London in February 1996. The article distinguished internet cookies as a potential threat to online users.
As explained in this article: "Cookies are the preferred method of accruing data because the information persists from session to session, and allows the Web server to recognize a user as having visited from the same computer as before."
These technologies exemplify a sort of precondition that is true for many online services to which we daily subscribe. It has to do with the arguments of risks vs. convenience; to participate in the convenience of online services we sign over bits of our privacy and anonymity.
3) GPS and Location-Based Services
"According to The Wall Street Journal, location-based services will be a $13-billion-a-year business by 2013, compared to $515 million last year."
Our mobile navigation and cellular services pose a threat to privacy because, in some cases, GPS tracking is used to inappropriately identify user's locations and is sold or given without user consent. Indeed, the problem lies in the absence of opt-out infrastructure.
Federal e911 rules require that cellular providers must, in the event of a 911 call, reveal location information in order to assist citizens in distress. The problem is that some users report that this information is being sent all the time! As discussed in another article: Verizon is defaulted to report locations of it's users at all times, but does, for those who care, provide an opt-out for locational privacy. The problem must lie in the fact that companies are not yet required by law to provide such an option which has raised considerable concern among users.
In addition, law enforcement should be required to obtain warrants in order learn the whereabouts of suspected persons.
http://library.cqpress.com/cqresearcher/document.php?id=cqresrre2009110600&type=hitlist&num=0