I'ts for real. They showed it on a documentary. The reporter gave them a 10 year old pic and did everything he could to throw them off. big glasses, baseball cap, had lost weight, grew a thick beard... He was in about 1 second before their systems rang an alarm with his name flashing up.
They work on things like distance between facial features. So unless you have your ears eyes nose and lips moved around...
The quality of cctv pics is very poor in the UK judging from the 'crime watch' so i doubt they can do that now.
But the day will come. Try walking down the street when you are wanted in 10 years time and you won't get 2 steps without the cops systems flashing you up.
The Sock