I think that you (and those unnamed "studies") should consult with psych people before coming to any conclusions. My understanding (from others, I'm an engineer

) is that the psych field is increasingly supporting the idea that most personality traits are learned through experiences, not inborn. So while there are obvious differences between the two sexes (the pumbing being an obvious one), I don't think we can say for certain what traits are learned and what are genetic.
So, what does it matter? I think the problem is that if we use our "common sense" to think about "these natural differences" (as you put it) we're likely to come up with conclusions that support our bias. As an engineer, I'm surrounded by male peers, many of them threatened by women in the engineering field, who confidently state that women should not be engineers because they are naturally bad at math and science. Maybe so, but maybe that is learned, girls aren't pushed in math and science like boys are in our education system.
You cite "volumes of scientific data" and "common sense" as your two supports for your (apparent) view that sex differences are inborn. As far as volumes of scientific data, I find that hard to believe without seeing some of it in detail. When the prevailing psych wisdom says that most traits (of any kind) are learned, why would the main differences between men and women be the total opposite. Secondly, it seems obvious to me that our society treats men and women very differently. I find it hard to believe that has no or little effect on their respective traits, when being raised differently affects most people in strong ways. As far as common sense goes, "common sense" is a term I like to use to describe support people use when they have a bias, but don't know what they are talking about. This is science, be scientific.
From a subjective standpoint, going to a large school in central Iowa, I've seen a wide variety of girls here. The more "traditional" girls who view the woman's place as mainly at home, who want to have some kind of traditional female career (nurse, teacher, secretary) if they want one at all (many are here to "meet guys"), etc, etc, tend to come from very rural, conservative parts of Iowa (they also voted Bush, strangly enough

). Not saying there aren't exceptions, but I've noticed more of a skew than randomness would dictate. Makes me wonder how much your upbringing has to do with "natural differences".
Edit: Said objective instead of subjective
