C.,
My daughter slept with my husband and I until she was 4. We got lazy and did not want to be up half the night with screaming child. When we moved, she was totally thrilled with a new room and made the transition beautifully. Our 14 mo old son now sleeps with us. Who knows when he will move out. my best advice is if you and your husband do not want her in the bed anymore to make a gradual, but consistent transition. And routine brush teeth lay down in his room, read a book, tell him goodnite give him a kiss stay in with him for maybe five minutes, say nothing and then go out. If he is screaming, go back in after like ten minutes or so, rub his back tell him goodnite and leave. If he keeps crying go in rub his back say nothing and leave. You may have to do this for awhile but eventually he will understand that there is no other option but to sleep. This will get tiresome, sometimes they are so strong willed it seems they can outstand you, it will be worth it in the end. If this seems like a lot of work for the moment he could always sleep with you. Remember that he will outgrow this someday and when he is 15 and wants nothing to do with you (hopefully this wont happen) you will have all the precious times he spent in your bed with you to hold onto.
Good luck!