Well, you have to know by now, the law of averages state the posting nazis will all post within ten minutes of the duplicate post. So, why not wait 20 minutes? Better yet, why not just let the admin know? Is there a prize I don’t know about?
Well, typically I like to let the poster know rather than posting to the admin, but that's just my style. Also, I will also give suggestions that might help with more effective searches in the future. I figure most duplicate article posts are unintentional, and try to offer helpful hints -- especially when the poster is a long-time FReeper who probably knew better but missed the prior post.