(For story highlights scroll to bottom) Story Highlights Airport security screeners' focus is shifting towards studying passengers' intentions Israeli companies have become leaders in developing security technology Systems can detect signs of emotional strain, which may signal a passenger's intent Other programs can study passengers' voice patterns for signs of stress Source: http://www.cnn.com/2008/TECH/12/02/airport.security/index.html
It's similar to a lie detector test, except they'll be using technology that allows them to perform screening remotely at a distance.
having cameras that can actively measure things like body heat, posture, and movement can definitely be a help. chances are the guy walking around stooped low, sweating lots and walking as though he has people watching him is doing something suspicious.