Getting on a "Best Place to Work" list is not just a matter of having great programs and practices. It's a matter of conveying this fact to whomever is compiling the list. Application processes for these lists vary, but nearly all include at least one invitation to describe your company's programs, policies and practices in an open-ended format.
In what ways is Mayer being held to a higher standard because she's a woman? Because she's a pregnant woman, a regrettable anomaly in the Fortune 500? Perhaps because she's a relatively young woman -- at 40, she's more than a decade younger than the median age of CEOs in the Fortune 1000. Or is it her femininity?