I really dont know how to answer that because my 3 year old still wears pull ups as well. My opinion however is to stop fluids at 6 and if you wake up diring the night, wake your child to go potty. A friend of mine just stoped putting a pullup on her daughter the same age as my son and ater a few wet beds her daughter quit wetting the bed. I think every child is dif. and it depends on the child when they are ready to loose the pullups at night. Some children actually cant help it, or have a medical condition, as for myself i continued to wet the bed until i was 11. Yeah embarassing right, and still until i was 16 would occasionaly dream i was on the toilet and wet the bed. In other words only you and your child will know when he is ready.
I am really glad to hear things are working for you and him!
Others, I am sure will have better answers. But the quick and easy is to limit fluids before he goes to bed - say no fluids (ok to brush teeth, etc) two hours before bedtime.
Also, does he have a night light in his room and the bathroom so if he wakes up, he can easily find his way to the bathroom? It is kind of scary in the middle of the night. Maybe even give him a cool LCD flashlight that he can use to light the way. I know that if none of these ideas work, then you can buy sensors that go off when he starts to wet the bed, and that is supposed to help (or scare the heck out of the kid).
Finally, realize that until last month, he didn't have to worry about peeing at night cause he had his pull ups on. If he is a sound sleeper, its possible he just hasn't made the connection yet. Will be curious to see what others have to say.