You get a smite for not acknowledging them! Just kidding. I haven't smote anybody yet, that would take a lot for me to do. But I really like that word: smite. And smote. That's one's fun too.
Anyway, I don't think any replies are necessary (I'm actually not quite sure what the etiquette for that is, either) because it would be like patting someone on the shoulder for patting you on the shoulder. Does that make any sense?