Okay I have seen this all over the place and have always wondered how they take these picture. The other day I was looking at a Creative Crate and she had a explanation of how it was taken. I tried it and it definitely did not turn out. Here is a picture of one of my first attempts under there direction. Note: I did not have my 50 mm lens so that certainly probably was one of the problems.
I tried a couple of time and then I told Steve what I was doing and after a few minutes he had it figured out. I really like how they turned out, I think that it would make a cool picture (watch out Melanie) at the Rupert square or where ever they have a ton of lights to show off the Christmas spirit. The key to making this work for us was having the camera on manual focus and then having the lights slightly out of focus- adjust as needed
This is what we had our camera set on: Manual mode Shutter speed 1/10 f2.8 ISO 640 Lens was 28 mm