How long should you wait before responding on someone's wall?

How long should you wait before responding to someone's wall post? Edit this page and add your thoughts.
*If you are a facebook addict, there's a good chance you will notice that someone wrote on your wall within minutes, if not seconds. Please don't respond within the first hour, especially if it's at night or the weekends (when you should be having a social life). If it's during working hours, then you can respond quicker, and if it ever comes up you can use the "oh, I have nothing else to do at work" excuse.
*If they ask you a question that needs an immediate answer, then answer it as soon as you can.
Category:Facebook Etiquette
Category: Wall Posts