I think people can identify with it more. Like a pp said, we are quite far removed from black and white pics; obviously that doesn't detract from the horror depicted, but the colour makes them seem more....I really can't think of the word! Can relate more? More relevant? (Excuse me; it's early!)
blueskypink you are right, it should not make any difference, and yet, for me, it did - hence the feeling shallow comment. Thinking about it, perhaps it is just the individuality of it. Whenever we see images of the holocaust, it tends to be numerous images. To take just one person and give a wee bit of personal history is perhaps all it needed - not the colour. I dont know to be honest, but I do find this colour image more impactful (if that is a word)!