I've seen it given to one member "Pony". I believe he was given it because some people were picking on him due to some questioning his experience, credentials, and English language challenges. So it was a way to say this guy is indeed legit, cut him a little slack. Thats what it looked like to me any way.
I'm just purely speculating on all this. Someone who actually knows may chime in. I'm guessing if they labeled him " A Rookie", TBTB thought that the people who were being hard on him might cut him some slack.