Probably because you typed a magical word. There are certain words that will automatically send your post the moderator land to be scrutinized. It has happened to me when the word ??ba?n or ??ban?ned, ?cen?sored?, what is perceived by the security software to be a link to a competing site, etc. Oh, almost forgot, remove the ?? for the magical words. Those are two that I know make the mods work for their pay.
I replied to a message by quoting the poster and it went to the mod queue because the quoted post qualified. The hijacked post usually will show up about a day later assuming you haven't posted something really, really, really bad.hehehe
A good example Mark is the thread you started in the DE Chapter: Is everyone originally from Delaware? ,
The first 3 posts are a good example of the qualifying words that work.