The explosion in user-generated content will enable organizations to gain previously unparalleled

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views of customers. This has important implications for user privacy—and presents excellent opportunities for marketers.

To explain: Both user-generated digital content (an appointment made on a BlackBerry, photos taken on a cell phone) and passively generated data (your Skype profile, your GPS coordinates as revealed by your mobile phone, your Google search history) leave real-time trails or logs. As more and more activities “go digital,” these data trails together chart patterns of user behavior. In some cases, a trail is apparent and part of the user experience; in others, people have a vague awareness of such a trail but don’t understand how it is used. Some data trails—say, the recording of your car’s license plate as you drive through the city—may be completely hidden from view.

In an increasingly connected future, the data trails from all these sources will create a massive universe of metadata. A new generation of devices will provide filters or lenses through which to view this universe. This technology will send constant signals that can be used in the aggregate. Even now in New York City, for example, taxis equipped with global positioning systems allow officials to study the migratory patterns of yellow cabs and come up with better ideas for traffic engineering. Alternatively, increasing amounts of data recorded from people wearing monitors for heart problems or diabetes can quickly reveal patterns of behavior among these populations in a way that long-term studies cannot, yielding a possible boon for the health care industry and insurance companies.

This is just the beginning. Soon it will be possible to view, sort, and mine these aggregations in new ways. For example, tools such as Google Earth, in combination with a cell phone that logs personal health parameters in real time, could allow an organization to, say, map levels of emotion in the population of certain city areas. If the Red Sox won a baseball game, data sent from a variety of tools could be accumulated to register tremendous excitement in the Fenway Park area of Boston. If you’re a marketer who can read the emotions of large numbers of people in a geographical area, you will know not only where to put your next electronic billboard, but also what it should display at the moment. Cheers restaurant, for example, might post an ad saying “Come celebrate!” or “Drown your sorrows.”

The ability to tap vast amounts of aggregated “people data” will have serious implications for behavior, ranging from the way individuals control their personal interactions and information to possible manipulation—for good or ill—by corporations and governments. All this raises fundamental questions about whom to trust with our data: Are you more comfortable backing up your digital life with your online provider or doing it off-line in your home? Which data set is more likely to be compromised?

Large organizations that have the ability to monitor aggregated data will have to resist the temptation to abuse it. Individuals and companies will need to find and walk a new line between serving customers and exploiting them, either way with pinpoint accuracy. In the brave new world of aggregated data, companies will need to monitor themselves as well.

Jan Chipchase is a human behavior researcher on the design team at Nokia. He is based in Tokyo.