It seems like something out of George Orwell: television sets souped up so they can watch viewers watching them. Last week Nielsen Media Research, purveyor of the make-or-break TV ratings, announced plans to develop just such a gizmo. The "passive people meter," a computerized camera system, would sit atop sets in thousands of households, keeping an eye on every move that viewers made.
The purpose of the system, which will not be ready for deployment for at least three years, is to get a more objective, precise measure of who makes up the TV audience. In the past, viewers in Nielsen...