More precisely, this service will only show you where the GPS device is...a bit pedantic, I know. But if, for example, a child is abducted (heaven forbid!) the first thing an abductor would do is remove the cell phone from the kid and ditch it.

Same with the kid who wants to go somewhere he/she is not supposed to: Leave the phone at a friend's house.

I'm not trying to be negative, but until the GPS is embedded in the child's skin, it's just a neat idea.