The Barabási study was funded by the U.S. Office of Naval Research (though it's unclear what their interest is), but Barabási et al conducted the research outside the U.S. because it would be illegal to use call records the way they did here. Researchers didn't go through the university research ethics review process because the Navy had decided that it was a physics study didn't actually involve human subjects and, it seems, because the way the experiment was run it was anonymous. Even so, plenty of people are up in arms about what the study means for privacy, and both the school and the journal have tried to defend the study.

But let's get to the question I'm really interested in. What was tracked in the Barabási study were calls and text messages, which enjoy a certain level of protection in the U.S. But in the U.S. every mobile phone is required under e-911 legislation to be capable of sending back to the mothership a fairly accurate location read, within 150 yards most of the time. And now comes the next generation iPhone, equipped with assisted-GPS that pinpoints location using a powerful combination of true GPS (which alone is accurate, I think, within something like 30 feet), cell tower triangulation, and wifi location data.

An expert I recently grilled on the topic tells me that the law on location records in the U.S. -- separate and apart from call records -- is a matter of some controversy and is still fuzzy. If a U.S. company, either carrier or location-aware app provider like Loopt or BrightKite, wanted to work with researchers on a study like this that used location data, would that be illegal here? Will keep digging...

(Photo thx Vagamundos)