My son came home at 9lbs 6oz. He was eating up to 8oz every 3-4 hours in the first month or so. By 6 weeks I started supplementing his formula with baby cereal once a day, which seemed to be more satisfying for him and he cut back to about 8oz every 5-6 hours.
He gained a lot of weight the first year, then evened off on his eating, thinned out, and sprouted up. He's now almost 21, and about 140 pounds dripping wet (he's about 5'11").
The pediatrician was against the cereal, I chose instead to listen to my mother.
On a side note, we adopted two girls at aged 4 and 9 from Russian that had been very malnourished. They both have problems with food - control issues - and while our youngest seems to have gotten the problem under control, our oldest has not and has gained a lot more weight than she should. We've talked to other parents in similar situations and heard the same thing - depriving children of food at young ages can be detrimental to them later in life, especially when it comes to their eating habits.