[sfem]

I always took gender to be what you feel you are inside with respect to male versus female. Sexuality is what equipment you prefer to have for sexual purposes. Transgender to me means you have the sexual equipment of one gender and the brain, heart, soul of the other to some extent. Transsexual to me means your equipment no longer matches what you were born with.
I hate labels. I don't like the transgender one because it still makes assumptions that are binary. Transsexual makes sense because it is actually fairly simple. I'm not sure having boobs is transsexual, although developing them smacks of it.