I identify as Queer because I have the capacity to be sexually and romantically attracted to people of any gender.
"Queer" is an umbrella term that some of us in the LBGT community use to describe ourselves. Most folks would recognize my sexuality as being Bisexual, but some folks consider the "Bi" in "Bisexual" to imply a binary interpretation of gender which is exclusionary to those who fall somewhere on the gender spectrum besides "Male" and "Female."
I was assigned female at birth (the doctors looked at my genitals and said "Yep! That's a girl!") and I identify as female, which means that I am Cisgender. Some folks are assigned one gender at birth but as they get older they discover that doesn't really jive with them which makes them Transgender or Genderqueer.
In an effort to consciously choose more inclusive language, a lot of non-monosexual folks (people like me who are capable of being attracted to more than one gender) have started identifying as Pansexual (like Miley Cyrus!) This doesn't mean we are sexually attracted to pans. It just means that we can be attracted to people from all areas on the gender spectrum, or, as some folks like to say, we're just big ol' sluts who love all kinds of gender/genital configurations.
But let's get back to the point. Why do I specifically identify as Queer?
The simple answer is that it's easier. There's a lot of back and forth between folks who identify as Bisexual and folks who identify as Pansexual. I love them all and I understand and empathize with arguments from both sides but what it comes down to is an exhausting debate that sets people at opposite ends of a fight I just don't want to have. Queer is not a perfect term (it originated as a pejorative for folks like us) but to me it feels full of solidarity and happy things. Rather than breaking people down into tiny specific labels it groups us together as one big Queer family and THAT is something I can get behind.