Of course, it is not taken seriously, for so many reasons. Women who stay home don't earn money (or at least they aren't perceived as wage-earners, even though many of them are), they are lazy, they live outside of the "real world," they are occupied only with children and chores, etc. etc.
More concerning, though, than the culture not taking the stay-at-home vocation seriously is that many times we don't take it seriously ourselves. Passion for motherhood is probably the exception to this. Most of the mothers I know who choose to stay home with their children feel very strongly about the value of that choice. But the choice to stay home extends far beyond children.
The truth is that women (and men) who choose to stay home have a unique potential to become leaders in our culture today, and we should take that potential seriously. By staying home, we have the opportunity to support our communities in a unique and vital capacity, strengthening the neighborhood, social organizations, civic groups, the family, and more. We are positioned to promote the alternative to Big Business and Big Government in our circles, providing some much needed balance in our communities. We will most likely be the "first responders" when people need help, encouragement, and aid--often a better social safety net than the best-intentioned government programs can offer. We can set an example in micro-commerce and education. We can mobilize when called upon for important causes. And that is only a portion of our contribution.
Staying home is a legitimate live-li-hood because it brings life into our cities and our culture. This is not to say that other occupations don't bring life--many of them do. It is only to say that we should take the "home vocation" seriously, and step into the leadership that is there for our taking. Because if we don't take it seriously, certainly the culture won't, and we all won't know what we're missing.