There are much discusions in other Forums about the word "noob". At the beginning the word "noob" was a phonetical contraction on "newbie".
So normaly that is not a insult (no bann for it i think).
But as all negatively connotated word it has quickly become popular in a human community of competition always ready to denigrate it's foes and opponents. So as everybody started to use it, its meaning has slowly evoluated to finally become an all around word to denigrate one's mate or opponent for any reason. In the end this global word is imo equivalent to "you suck".
So i think it's all time only how a player will understand this word. Noob can be a reason for Bann but only if he use it more times and if the context means more that u suck and not that u are a newbie

I agree. Usually I don't give any ban for "noob".