Well, given enough time, women will prefer men who provide more advantages to her children. Of course, "earning potential" actually doesn't matter much either,

Well, given enough time, women will prefer men who provide more advantages to her children. Of course, "earning potential" actually doesn't matter much either, in a wealthy society where death from poverty is rare. Instead, look at the people who are having lots of kids vs. few or none. Don't underestimate the power of vertical memetic transmission, either--breeding rapidly is more viable today than ever before as a means of promoting ideas. Genetic engineering will probably throw everything out the window long before selection pressures could do much anyhow.