"Currently, an amendment to the Federal Reserve's Card Act rules that took effect last October requires credit card issuers to consider applicants' individual income instead of household income when making lending decisions. So stay-at-home moms and dads who rely on a spouse's income may have a harder time getting approved for cards on their own, even if they have perfect credit."
I'm guessing it doesn't matter if you are a parent or simply a spouse. But the thought did occur to me that what if your only individual income is your 401K, how do you specify that monthly in a credit card application? If your spouse is working, you might not even have to turn any of it into income.