I agree, nice shot - and the background is blurred nicely.
But this lens is tricky (I have the very same lens, and love it).
You need to learn to control the DOF carefully - with this lens you can have the depth of field very shallow if that's what you want, so part of using it is selecting the appropriate aperture and distance to subject. I would have liked to see the girls eyes and the puppy in focus whilst blurring the background. To me the girl's face looks a little warm - I might not have gone so far on the white balance, but maybe if her face was in focus it would look better.
