n00b, don't help. Or do, but help to string them up by their ankles and beat them
Newb, help as long as I'm not particularly doing something else or on a vendetta against someone.
The distinction is this: If n00b is fighting alongside you, and you save their ass (flank, throwback a grenade/ w/e), they will just run off. A Newb will thank you.
If you offer advice to a n00b who's getting annialated (a sniper "keep moving, it makes you harder to hit"), they will have a go at you. A Newb will take your word (as the more experienced player) and take it into consideration.
and finally: The round has finished. You fought against significantly better players, and got your ass handed to you. A n00b will let off a volley of swears at HIS OWN TEAM (the ones that lost), before ragequitting or swapping teams. A newb will ask if there was any problems with what they were doing, and can they do any better.
Actually, there was a definition on a thread the other day that I read... "A n00b is a player who refuses to learn how to play better from others. A newb is a player who has not had the chance to learn yet."