I'm new here too! I'm used to the lack of single defining characteristics because I'm knee-deep in giftedness, which is another blurry concept with some really complicated biological basis. My best friend came out as FTM to me the other day, which is why I'm here, but the androgyne thing looked interesting... my main response is, "Aren't most people like that?" as in non-binary in gender, but that may be because, being exceptionally/profoundly gifted with a history of related mental illness, not to mention bisexual, I tend to get along with the misfits. (Plus, I've read in a few places that the gifted are more androgynous than the regular population...)
I took about half of the first test someone (riven?) posted before stopping in frustration because of its simplistic evaluation of mainly right brain/left brain strengths. While those things are related to gender, they're hardly the determining factor, and I wouldn't say every woman with a style of thinking that's more common among males has to forfeit her femininity, or vice versa. Err, well, really I quit because they wanted me to measure my hands and I (a) don't have a ruler and (b) have a connective tissue disorder that messes with those proportions anyway.
I've used the term bigendered to describe myself even though I hadn't heard the term. Over the past year or two (I just graduated high school last month) I struggled with not seeing males as superior to females (I'm in a female body--I bet I'd do fine in a male one, too, but it doesn't matter to me) and I guess masculinity still seems a little bit more "comfortable" to me in general, but it's a marginal difference. I've also described my attitude as anti-gender because I don't see any real reason to pay special attention to gender's polarities, and all the teeny tiny prejudices, jokes, baffled looks, etc that get applied to steps taken against the stereotypes are so damaging, and if they didn't exist, there'd be no friction preventing transsexuals from sliding over to their preferred point in the gender space.
