Genderqueer is the modern term to describe just about anyone who doesn't fit into society's concept of normal cisgendered heterosexuality - i.e. boydykes and genderfucks and drag queens and all us other sundry freaks.
Genderqueer is the liberating realization that there is more to the world than binary classifications - straight, lesbian, female-to-male, et cetera. It's the stretching of the concept of queer - the idea of an infinite variety of sexualities - to gender. Just like there are guys who call themselves straight but like to suck a little cock every so often (that's queer) there are dykes who pack dildos into their pants and call themselves men. That's genderqueer. It's the recognition that there isn't even a continuum - it's way more complicated than that.
Gender, sex, and sexual orientation are three things. And while they correlate strongly in certain ways - for example, there are lots of people with penises who like to fuck women and call themselves men, and people with vaginas who like to fuck men and call themselves women - there's lots of others too. When I say I'm genderqueer, that means that I'm not gay, I'm not transgendered, I'm me in my uniqueness and sexiness and dammit, your categories don't cut it!
That's the subversive thing about genderqueer - it rejects the idea that a person needs to identify zirself with a group and instead acknowledges that if a boy goes out, looking like a boy and wearing nailpolish and mascara, it doesn't mean he's gay, it doesn't mean he want to be a girl, it just means he likes nailpolish, and maybe also subverting the dominant paradigm. | 
