'fanboy' is just a term (usually derogatory) referring to people who are obsessed about following something, be it sneakers, anime, clothes, or whatever, to the point where it gets obnoxious. Case in point: people lining up to buy stuff, overly trendy items like Number (N)ine Fender monogram tees being sold out fast, etc. A lot of it is a result of magazines and celebs hyping up an example for these youngsters to follow, when I guess they don't really think of an original style that defines them.
More on the lining up phenomenon, i think it really destroys the scene for people who want to get things at retail price. Like with sneakers a lot of kids line up to re-sell, making obsessives have to pay a lot of times twice (or a lot more) retail to buy these items. A lot of the Japanese brands are sold at parelle goods (i think that's the term?) shops where the stuff is marked way up after being bought from Japan. Then again it's just the tees and small accessories...it's good that Joyce has bought in some more advanced items from runway presentation.