Here's an interesting article from someone who argues that dual-incomes have lead to lower incomes for each individual person.
He also touches on other interesting points:
"When I was in junior high school in Japan, I read an essay in a textbook by a Japanese woman who was critical of American feminism. To her, the American feminists cheapened the value of the traditionally female roles by implicitly assuming that traditionally male roles were nobler human endeavors. Instead of focusing on the value of traditionally female roles, they all focused on their rights to take on traditionally male roles. In that effort, they reinforced the notion that traditionally male roles were superior."