I used to work at a vw dealer and ALL the VW brakes squeak! It's a combination of brake dust and condensation on the rotors. The new brake pads that are used these days are metallic, therefore the dust is metallic. You'll probably notice that your brakes squeak mostly in the morning when you're first backing out of your driveway. When you go to drive your car the next time, have look at the rotors and see how rusty they look. Thats from parking your car with hot or warm brakes and when they cool down they collect moisture and form surface rust. The first few brake applications are cleaning off that corrosion making squealing or grinding sounds. To get rid of that noise, you need to: A. Wash your car with a pressure washer and spray off the rotors while doing so. B. You can try going to your local parking lot and tapping your brakes while driving backwards or sometimes forwards works too. Backwards is not the normal rotation direction so it may knock some grit loose that at normally wouldn't going forwards. It's worked for me, worth a try. It's not just VW that has squeaky brakes either, it's most new cars with metallic pads. I just had new brakes put on my Ford work van and they squeal like hell.
I posted this on another question, but I know most people are frustrated with it, so I thought i'd share.