Alright... there has been a ton of sayings and slang over the years. I think my favorite is still pwned... you just don't see or hear that anymore. There have been other very annoying phrases.
Another one I thought was funny that I've only heard a couple times --> Your face has been rebooted, sucka! :))
What is your favorite? What was dropped off? What were you happy to see go away? Thoughts, comments... post it up!
Bio break - frequently seen typed out on WOW raids, haven't seen for years now (although I've not played an MMO since)
smurf - still seemingly used, but clever nonetheless
frag - kinda died after the doom days
zerg - heard it prior to google explaining everything I didn't understand, I think I asked the chat and got called a noob (also slang but I'm not honoring with a mention)