I just can't get over how "Fanboy" carries the expectation of extremely pretentious criticism, and "Fangirl" carries the expectation of starstruck gushing silliness.
I know what fangirls are like. They are exactly like fanboys when they get disappointed. I know what fanboys are like, just a goofy as fangirls when they get starstruck. Its just an inescapable connotation.
We need a gender-neutral word, dammit, and "Fan" is just a tad too dignified.