i thought the meaning of "n00b" was unoficially changed there about two years ago...
it started as an acronym for "newb" ( acronym... is that the right word ? ) anyway, it started as that, but individualised itself, because...
if you were seen to be doing something stupid, or annoying online, most people clocked it up to you being a "newbie", ( for example, doing something wrong in Command and Conquer or starcraft or warcraft or some online game that meant your losing the match, OR talking bollox and asking simple questions ) however repeated acts of moronity despite you not being new, garnered the name "noob"
so...
noob / n00b = general moron, annoying bastard, etc etc
newb / newbie = someone who is new to something, and can thus be pardoned for stupidity, because its really just inexperience
... dosn't really matter to me, because i hate the word n00b, i prefer to just call someone a bollix...