DD gets smacks now and she is almost 4. Not often. Maybe once a week if that. But i dont think it serves its purpose anymore. I think the threat of having things taken off her is more of a better "use" of punishment.
She has a blankie that she had had since birth and lately ive noticed the threat of that being put away for 2min is more horrifying to her then the idea of me giving her a smack Even when she doesnt even know where blankie is anyway!!!
I put it in the cupboard the other day because she kept trying to give it to the puppy, i warned her he would destroy it and she should pick up all her toys so he doesnt get them either. She didnt listen so i put blankie away to save it. She went and cleaned up all her other toys, put her dirty clothes from the clothes basket into the laundry made her bed and tidied her books then politely asked for it back.