To me it looks like some lensbaby/soft focus lens. You can use flare and whatnot to enhance that look. However, you're also looking at very careful deliberate lighting techniques. He may even be giving some fill in there or using natural reflective surfaces like buildings. The bodies are generally nearly backlit by sun but off by a few degrees so the rear of the head gets a nice accent to it. If the careful choice of scenery and lighting don't get you there, you can try a fill flash or reflection to even out the light because something tells me it doesn't look like that on it's own.

http://3.bp.blogspot.com/_fHt1JYhaJA...s1600-h/13.jpg

Looking at that image, compare the shadows. Something is weird in the lighting. The shadows of the people are black while the shadow of the building is pastel blue. Something's off...

The first images are also very well lit, with an even fill. I think lighting is going to get you closer than screwing with film types.