Facebook automatically creates a page about you and your spouse based upon your "Married" status. This is one way to see what you and your spouse really have in common.
It's there, whether you approve it or not. Some people find it creepy. I find it interesting.
HOW DOES IT WORK?
Facebook takes your profiles' Relationship information, combines all the things you and your spouse have in common, and then creates a Couples Page. If you don't like it you'll have to unFriend your spouse or remove him/her as your spouse.
However, one thing I have to give credit to Facebook for is that the Couples Page respects both you and your spouse's privacy settings in conjunction.
To see your Couples Page, log in first, and then go to facebook.com/us