I tried the effect myself a few days ago, and I must say it's difficult to achieve.
You have to have the right circumstances to do it. The sun in the right angle, the model at the right angle and the photographer to.
Maybe most importantly (and my hat goes off to you for that), the right time of day. I don't know where you live excacly, but the sun only is in the right angle during the morning or evening here.
And in the summer that's VERY early and VERY late.
I's also dangerous to get blinded if you aren't carefull. Are you wearing sunglasses? Cause I know I am going to from now on!
I just have one question... what kind of Photoshop action do you use? Levels? Curves? Gradients?
Cause you have a really "cool" effect there, lots of blue and purple and white.
One of the reasons I'm such a fan of your work: even without all this, the pictures would still look beautiful.
If you ever feel like it, try to use a flash or even without the sun. I'm sure you would still be able to achieve great results. (just don't do it in full sunlight please... unless you really know what you are doing. ^-^)
You are doing great!! Keep at it!