We definitely have lots of jargon to go around, from LFG to twinks to PuGs and a lot more. But what's most interesting about all of these answers, to me, is the way it spreads. There's a little bit of Googling and research going on, but really it's a very social thing -- you see "wtb" in the trade channel, and then you ask someone you know what it means (rather than looking it up somewhere else). Thus, definitions of the terms are very organic: "pst" could mean "pssst, here's a whisper" or "please send tell," and yet because they both mean the same thing, both meanings propagate. Likewise, usage tends to be a very social thing -- the person who types "LFG strat need heals" won't type "would u like 2 go to strat?"