My son gave up his first night feed at 6 weeks, meaning he slept from 11 or so until 5am or so - maximum of 6 hours. I completely followed the guidelines in the Baby Whisperer for him. I found that his 2am-ish feed was only to suck on something (when he was about 6 weeks old), and not to eat, as he's only have *maybe* an ounce. So that's when we gave him a dummy for the first time. We only ever gave him a dummy in the middle of sleeps so he didn't have to suck on a bottle - once he got his thumb (around 8 weeks) he skipped that 2nd night feed and went from about 10pm to about 8am. He still woke up at 2 am for a few nights, but once the dummy was on he fell back asleep. After a few more days he just slept through entirely, not waking up for the dummy at all. The BW book recommends a kind of topping up method once they get to be about 10 lbs and are taking at least 20 oz a day. So you feed every few hours as normal during the day, but before beftime you feed every 1.5 hours, or even every hour, to top them up with enough food to get through the night. I'm explaining it really poorly, but we followed what she wrote in the book. (Well, Philip did anyway). Of course it didn't happen exactly like that, for ages he ate a few ounces at 7,8, and 9, but then would sleep for 8-10 hours - where she recommends going every 2 hours. She makes a point of making sure they get plenty during the day (he was getting 24 oz or so a day), because if they get that much they don't physically need the food at 2am, they are doing it out of habit.
Hope that made some sense. I'm a real fan of the baby whisperer. Like *any* book about baby care a lot of it is crap, and you really have to adjust it for your baby, but what i like about her is that she says that. Her main point is getting to know your own child as their own unique self, and urges you to use your instincts, at the same time telling you what most babies she's taken care of have needed or been like.
Sorry if it sounds like i'm totally plugging her - but I've have a baby who slept through the night since he was 6 weeks old, and at 8 weeks was solidly doing 10, and he now does 12 without exception. Not all babies are the same of course, but it worked for us.