I didn't get it because I didn't get why it was a joke. I mean, I got the whole dirt-mud connection, but I still didn't get why it was funny. I guess it didn't work on me because I was thinking, "dirty joke", while "a pig fell in mud" is... well, just a sentence with dirt involved. I think the whole "the jokes on us" thing sorta passed my mind.

Oh yeah, and I just clicked on this because I was really confused on why of all people and in all places, an admin-ey mod person would post a dirty joke on a kids site. And that was the only reason. Really. That's all. Seriously. For no other reason. Yep. No other reason. What? Why are you all looking at me like that? No other reason. Heheh.*eyes dart*