The real bottom line is that in my view, the Supreme Court is likely to come down on the proposition that "natural born" as used by the framers in the Constitution means born in the geographical United States. I think that continues to be the general view of most of the Constitutional lawyers who have looked at the question.
I think you’d be interested in this law journal note (it’s only 18 pages long), which analyzes all of the precedents and interpretations surrounding the Natural-Born Citizen Clause: http://yalelawjournal.org/2008/03/03/citizenship.html The article concludes that a person with the right to U.S. citizenship at the time of his or her birth is a natural-born citizen for purposes of presidential eligibility.
Of course, reasonable minds may disagree, but I would be shocked if federal courts ruled that someone that is a citizen at birth but was not born within the geographic U.S. was not eligible to serve as president.