I do see this point, and I've already seen that sentiment expressed by HRC supporters.  My problem with that argument (and I know you're not arguing it, you're just stating it) is any woman that Obama picks is just being picked because she's a woman?  For a campaign that's been crying sexism for a while, it's a bizarrely sexist argument itself.  While clearly her gender fits into the picture, she's highly qualified and has been for a while as you pointed out.