I have a 6 month old who LOVES her paci, so I can't answer this as a mom. I CAN however, answer this as a teacher and child behavior management specialist.
The kind of plan you develop to get rid of the paci will greatly depend on the personality of your son and how well he responds to positive/negative reinforcement.
I would absolutely recommend beginning with a positive behavior plan, and at his age, it would require some sort of tangible reward. Kids his age love the good ol' fashioned sticker chart. Make one up on your computer, buy a package of those gold foil stars, and a particular item he's been wanting for a while.
Then set up something you think would work: If he goes without his paci for the whole morning, he gets a star. If he goes without it a whole afternoon, he gets a start. If he goes without it a whole night, he gets a star. When he earns 10 stars, he gets his toy.
This is just the first idea I had...if it doesn't work, it can be adapted and changed to fit his personality.
P.S. Some people will say having him work for a reward is "bribing" him...they will say the desire to give up his paci should come from within him. Obviously, that would be ideal, but it's not where he's at right now. And as far as "bribery" goes...we all work for rewards. I love teaching, but wouldn't do it from 6:30 in the morning until 6:30 at night unless I was getting paid. We ALL work for reward!
Let us know how it goes.
Edited to add:
Oh!! I just looked in my Babywise book, and they suggested using a needle or scissors to poke a hole in the tip of it. They say it reduces the pleasure/soothing and kids usually just give it up on their own after you do this. It's worth a try!