In 25 years of using the arpanet/Internet, that's the first time I've ever seen "copyright" in a description of "Netiquette". Priority, attribution etc, yes, but never copyright.

The "Dear Emily Postnews" columns were well done but apply more to the usenet era than message boards.

Perhaps the biggest thing is to remember that for many or most readers English is not their primary language and that's not always immediately obvious. And subtle pop references are often pointless to readers who didn't grow up immersed in American TV culture.