Well... some people won't agree with me, but I will tell you how I got my baby to sleep through the night at a very early age. You have to be very consistant. I would never let my baby sleep on me during the night, only during day naps. I got all the extra cuddling in all day long so that at night he could learn to sleep on his own. If you get him used to sleeping on you of course he will prefer mommy.

But soon he will get bigger and hurt your back so you should break the habit, at least at night, now. I remember it wasn't long before my son started hurting my back during day time naps on mommy.
First, I made sure the lights were dim around the house at night so that he could differ between night and day. Then, at night we would feed him, change him, and put him right back to sleep. We would never talk and never play with him no matter how awake he was at 2 am. I would never take him out of his room to the kitchen. For the first 2-3 weeks he would be awake at all hours wanting to play, and sleep during the day etc, but we refused to play at night and were only really boring. I also had to let him cry, which was really difficult, but my husband and I supported each other through it. It was hard to let him cry, for both of us, but it helped him learn to self soothe and get to sleep. I NEVER rocked him to sleep. I never put him to sleep with a bottle. I always laid him down awake but drowsy. So we would feed him, change him, and lay him down to sleep. Then if he cried, which he did, I would wait 5-8 minutes and go in and rub/scratch his back and say "its okay.." (really soft) or say nothing and then go back to my bed. I would lie there awake and wait 5-8 minutes, do it again. I would do that until he fell asleep. I got no extra sleep this way in the short run but in the long run it was very effective. IF he got really worked up(major crying) I would pick him up out of the crib and get him calmed down and then lay him back down. It was really really hard to stick with it, and I know some parents would say I should have stayed up all night and been available at his every whim and call but I don't believe that. I believe that my son can be supported, loved and know that I am there for him any time he needs me, without my needing to stay up every night all night for the first three years. I get frustrated with parents who have stayed up every night all three years and then get angry with me that my baby sleeps through the night. At night, I fed him and changed him, that's it. I rubbed his back. I love him completely and I did this as much for him as for me. Now at 10 1/2 months he sometimes wakes up with a start and cries. I wait a minute and usually he goes right back to sleep. Sometimes he needs mommy to come rub his back and say, "its okay.." but he doesn't need me to rock him, sleep with him, make an extra bottle, get his pacifier from where it fell out of his mouth, etc.... because those are not things he learned puts him back to sleep. His crib is his safe place and he looks all cuddly and relaxed when I put him in there at night. It was worth the crying I went through in the beginning to see him now....