The thing I read didn't specifically say marriage. I saw something about it in a Q&A, I'll look for it.
Edit:
Oh, ok, it did specify marriage.
Will we be able to have relationships with the NPCs, romantic or otherwise?
Bruce: Absolutely! You make friends with people by doing things for them. Friends in the game will treat you differently. Some of them will even agree to go with you into dungeons and on adventures. You can even get married. If you own a house, your spouse will move in with you.
I've heard plenty of people whining about the concept, something about Fable I think (which I haven't played). I don't think it's a big deal though, just don't do it if you don't like it. It's just an extra element of realism for the hardcore roleplayers.
Or it could be a way to add more life to your house. I know my house was just a loot store and not some home base or anything.