Edit: It's probably not a good sign that they have two directly contradictory statistics for the amount of US private wealth controlled by women.
http://www.catalyst.org/publication/256/buying-power
http://www.she-conomy.com/report/marketing-to-women-quick-fa...
Whether the top earners are men and the huge disparity on Bill Gates/Larry Ellison level wealth do not matter at all in this discussion.
Advertisers and companies are not competing for THOSE people's money (except if they make private jets and luxury cars), they want the money of the average household. 100,000,000 families have brought Apple products, for example, and all of the top 1000 wealthiest guys just bought another 1,000-10,000 combined.
So, when they say they control 51% of private wealth, that might or might not be true overall, but it is very true for the kind of wealth that matters to companies/advertisers. And it is even more true that women also influence what the family will buy, even more so than men.
That's awfully meaningless without the partner stat. If you stop and think about it, women and men could both "Make or influence" 85% of all purchasing decisions, at the same time.
I see far too many blog posts and junk articles posted as sources or evidence in this day and age. No references to studies, or exposed facts that were collected by census.
Just someone else who cracked open Wordpress and says 90% of people do something 10% don't.
Perhaps that's because the evidence has already been stated clearly?
Here are the stats:
"Women account for $7 trillion in consumer and business spending in the United States, and over the next decade, they will control two thirds of consumer wealth.
Women make or influence 85% of all purchasing decisions, and purchase over 50% of traditional male products, including automobiles, home improvement products and consumer electronics.
BUT 91% of women say that advertisers don’t understand them."
(via http://thenextweb.com/socialmedia/2012/01/24/the-top-30-stat... )