I don't know if this should go here but just move it to the appropriate place then :P
So here goes, my guild leader just finished talking to a GM and tried whispering him again but got a whisper from "System" stating that the GM was unavailable.
So if you log on to WoW and try "/whisper System <Message here>" You will whisper Blizzards system bot, it doesn't reply and nobody reads it but it's still pretty cool and it has the Blizz tag in front of it.