Ladies how long does it take you to say something after your new hair-do goes unnoticed?

Why is that so important to you? I guess its right up there next to loss of weight. I had a co-worker at one time who already looks nice. She got a new hair-do and went phishing for compliments. Come up to me and say, "you know they tell me I look like Halle Berry when I get my hair cut like this". Do you think this is tacky? Does it hurt more when when females friends/family don't notice or the men in your life don't notice immediately?