Scott Richert makes a compelling case that the Palin nomination is an assault on the Christian understanding of the distinctiveness and complementarity of the sexes.  Aaron Wolf discusses the Palin choice in relation to abortion and foreign policy.  Thomas Fleming observes:

If Ms. Palin is a truly a Christian conservative, she is certainly not a conservative Christian.  Christians are supposed to understand the implications of “male and female created He them” and, at the very least, realize that a mother’s primary obligation is not to the taxpayers but to her children and husband.  It is all very well to celebrate her prowess as a politician and moose-hunter, but I do not recall these as feminine qualities in the Scriptures. I or we are not saying that we cannot vote for a woman who did not stay home to take care of her family, but only that this decision is incompatible with traditional Christian morality.