How long did you have to do it for? I mean in terms of how many months / years before they didn't need it anymore rather than how long you were rocking before they went to sleep (though that would be interesting too!)
DD (4.5 months) won't feed to sleep except for sometimes in the middle of the night, nor will she settle herself except in the car or sometimes in the pram.
I rock her to sleep at bedtime and whenever she's tired in the day and I love doing it - it feels very natural and I like the closeness.
...but - I suppose what I'm after is some reassurance that I won't still be doing it when she goes to university!