nOOb = any level character that exhibits a lack of understanding about the basics of FFXI in general. In other words they're stupid.

newb = a low level person.

I'm still a newb @ 45 I feel. But i stopped being a nOOb around lvl 25 or so.
I remember when I first got on it took me a while to get down the difference between /tell, /shout, and /say. I was in Windurst Woods /shout-ing to my friend in East Sarutabaruta.

/shout Kenoa why won't you answer me you prick!