Where is the line – and how do you convey that to new recruits?

We’ve had a couple of new recruits unceremoniously crash and burn due to making completely inappropriate comments in guild chat.

The problem is – every guild culture is different.  Our members definitely flirt with the line, but they know where the line is.  I’m not sure how a new member is supposed to know where the line is. The obvious answer is to shut up and listen for a while – and if you’re not smart enough to keep your head down and do just that, then you’re just too dumb for the guild!

I was trying to explain it to the husband, and finally I came to the conclusion that it is OK if the off-color statement stays in the game world, but is inappropriate if it is directed against a specific person or references RL too much.  I’ll give some examples:

OK: Jokes about in-game features

Example: “Look at my Giant [Penance]!  You have [Penance] Envy!”

Example: (on twins) “There were two balls coming right at my face!”

Example: “The boss’s crotch was right in my face and he didn’t buy me a drink first.”

Example: Racism against gnomes or other in-game races.

Not OK: References directed at harassing or insulting any given person or group (that get too “RL”).

Example: “Prove that you’re a girl!  Boobiepxplz.”

Example: “I’d be happy to show you what I’ve got (in my pants).”

Example: “I bet you’re one of those people with the stupid (insert opinion here) bumper sticker on your car.”

Example: Racist comments against real races (not gnomes, tauren etc)

Where does your guild draw the line?  How do you communicate that “line” to new recruits?