Well, given the answer to the last question, this one gets a little different. Really, it's more What changed your previous viewpoint? The answer to that is: I've always maintained that personality is far more important than a person's physical body. I had thought that mostly with respect to body shape rather than physical sex, but that's definitely started to change thanks to falling hard for my best friend, who is also male. I had never entertained any thoughts or fantasies about males until then, but since that, I've had them about as frequently as ones about females.