it will be harder to transition them out into their own room as they get older. no they wont be in their 20's and still need mommy and daddy in the same room with them, but when their young, you will be in for a battle!
my brother and sister inlaw have two kids, and they BOTH! sleep in the same room with them still. my niece is 7 now and puts up a big fight when she is told she will be sleeping in her own room tonight, she is afraid of being alone, even though she's not really alone-her parents room is right beside hers. my nephew is 5 and he puts up a little fight too, but will go in his room and if his mom puts a movie on he'll fall asleep in his room no problem.
but my niece always ends up getting her way and sleeping in her mom and dad's bed.
i think they waited a little too long with her to get her to sleep in her own bed, and the only way to break it now will be to let her cry it out. but i dont think they will do that anytime soon.
my son and i have naps together, hes 6 months and in the day time, when he goes down for a nap i will lay down beside him, our bed is big and i am never fully asleep just relaxing and watching a show.
he sleeps in his crib at night time all through the night, and turns a little too, then again, his crib is in our room, but when we move him into his own room i dont think he'll notice much of a difference because he will still be young.
maybe you guys could bring her crib in your room if thats an option, or take shifts to check on your daughter throughout the night, like every couple of hours or something if your husband is a little paranoid leaving her on her own.