Quotes going back as far as Plato have remarked that society is declining. It isn't.

Wanna bet?

I almost, almost responded to this with a query asking if you, my brother, were in anyway upset or perturbed, only with no account given to spelling or grammar.

I've had experiences like this before as well, with PuGs or part-time guildies being abrasive or simply outright offensive with the intent of causing distress or anger among regular guild members. Sadly, these people were often savvy enough to wait until an officer was unable to see such actions, or simply waited for the best time to take what they could from the guild. There is no easy way around it if they're persistent. Just tell a GM. They take things like this seriously, and they will mete out justice.

As for taking legal action, it's possible that they could sue him for slander depending on what he posted on the website, but I'm not sure. Is there a lawyer in the house?

I'd actually counter by saying that as social media and such get bigger and bigger people are starting to realize just how real a virtual interaction can be. There are kids that have been on Facebook for literally their entire lives (I've seen more than one pregnant mother make a Facebook for their as yet unborn child). While the social conventions of Facebook aren't exactly the same as real life, they're leaps and bounds better than XBox Live.

Cultivating an online personality (even if it's under the name xSephirothx instead of Joe Schmoe) is becoming more important, so I expect the population of dickwads on the internet to gradually decline to roughly the same levels as real life over the next few decades.

look up "Greater Internet Fuckwad Theory." - it's circa 2004. And believe me, it was just as bad if not worse in the 10 years before that.

Society has been going downhill since the third caveman turned up.

10 years before 2004? no it wasnt this bad