AT&T Says It Will Now Sell Your Anonymous Usage and Location Information to Third Parties
Don't worry about being tracked, AT&T says this data can't be traced back you individually. An example AT&T gave is that of an election.
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"After an election in your community, officials will release the final vote tally. They might say that 60 percent of the voters picked Candidate A and 40 percent picked Candidate B," AT&T says. "That information is a type of aggregate and anonymous data. It’s 'aggregate' because it combines information for the whole community telling you who the community as a whole voted for, and it is anonymous because the data doesn’t tell you who voted for which candidate. In the Internet world, aggregate and anonymous data can be used by retailers, advertisers and marketing companies to figure out what consumers want in a particular area. You benefit by having better products available and seeing advertising more relevant to your particular consumer segment."
If AT&T's explanation doesn't give you warm fuzzies, especially in the wake of all this NSA spying stuff, you can opt out of its aggregate and anonymous data collection. That doesn't mean you won't still get ads, or even fewer of them, they'll just no longer be targeted.