After Andrelica was retouched and the grey seamless masked out, a texture from Mark S. Johnson (http://www.msjphotography.com/) was placed behind her:
You could stop here, a take it a step further. Add a new blank layer above the texture layer, and draw an oval behind the model. I filled it with blue, deselected it and gave it a 1,000 pixel Gaussian blur:
Beyond this, one could give the texture layer a very slight blur, and a vignette could be applied.