With DD, I always nursed & rocked her to sleep when I was around, but eventually, somewhere between 9 months and a year, she stopped nursing totally to sleep. So then I started putting her in the crib drowsy but awake, with one of her crib toys on. Sometimes she'd throw a big fit and wake up, sometimes she's wake up and turn on her crib toy again, sometimes she'd just go to sleep. In the middle of the night she almost always just went to sleep. We never coslept with her; neither she nor I could actually sleep if we were listening to the other.
With DS, he was less nursing-oriented from the start. I do mostly nurse and rock him to sleep, but one day around 3 or 4 months I nursed and rocked and rocked and nursed for 2 hours at bedtime, got horribly frustrated, and put him in the crib with the lights off and the mobile on, while I took a break. And he went to sleep. So sometimes he'll just... go to sleep. (At least until he started rolling around the crib, but I suppose he'll settle down when that gets old.) He also goes to sleep in the car, and I can put him drowsy-but-awake in the swing and he'll often fall asleep. And at night he will fall asleep cosleeping and nursing. I've made a real effort with him to encourage a variety of sleep locations, but really, I think he's just easier because he's much more mellow than DD.
I know this doesn't help to say, because I never believed it myself before DS was born... but your second really won't just be a clone of your first.
