The term tends to be used as an insult, either because someone is inexperienced at playing the game, or simply goes against the almighty 1337 players' ideas. It happens on forums too, with people making understandable errors/going against the grain and getting flamed for it.

Newbie-bashing is an unfortunate side of web-culture that stems from status-obsessed jerks with inflated egos, and because it is so common terms like n00b can often be interpreted as offensive, even if they aren't meant that way.

As Ouch! and Mindflare said, use the politer 'newbie', which is a much friendlier term. Most new players are happy to admit that they're inexperienced or need help, but they'll probably be worried about getting flamed. If you make it clear to them that you don't want to yell at them, I'm sure they won't mind.