E.,
I've gotten so much different information, but the stuff that makes the most sense to me is to not expect more than 5 hours when your baby 'sleeps through the night'.
Breastmilk digests much faster than formula and solid food.
What I do is put him down just as he's starting to get tired - I nurse him to sleep. He wakes generally in 3-4 hours, and because he is teething, sometimes more often than that.
La Leche and other sites out there (I wish I had them handy for you!) mention that they are less concerned with sleeping solid through the night (and very concerned with a baby that sleeps too much!) and to expect that a baby will want food and comfort.
Above all, all babies are different.
I don't keep a schedule - my son goes down usually when he is most tired, and when we have to be out (for whatever reason) it means he is up for a bit later than most usual kids. Generally he sleeps 8-9 hours with an early nap.
Example: Last night he went to sleep earlier than usual, just before 8. He was up just after 5. He took a nap around 8.
I know this is probably not what you're looking for - but I've spent the wrong time this side of pregnancy finding out about sleeping issues. I should have looked all this up before hand - but then I figured I knew what I needed to know then. HA!
Mostly, this is what works for us. I think if I kept him to a schedule, it would cut out Daddy time (2nd shift) one way or the other.
Good Luck,
Let me know what you decide,
M.