Although I think it would be cool, I don't really foresee them allowing married couples joint housing. Mostly because of how simple the marriage system sounds. YoshiP said that you could "divorce" by simply throwing the ring away. And if it's that easy, I don't know, it seems like they wouldn't attach housing ownership to it. But I could be wrong! There is a lot I would love to know about personal housing still, I can't wait until they finally release some info on it.