This is a beautiful image. Very good pose and very good lighting. The lens is also my favorite portrait lens and this picture confirms it once again.
I agree with both of you that the arm in the bottom right is a little bit distracting, but I believe you could crop the bottom of the image a little bit and it should then be ok.
After all the model's face attracts most of the attention.
Antonio, thank you for your in depth comment. I agree with you completely, the arm bothers me too, but I couldn't do (or didn't know how to) anything about it. Crop would spoil the photo in my opinion, cloning off the arm also wouldn't work... If you have any suggetions how to "repair" this flaw, please let me know (or anyone else;)).
good trick to enrich a nice portrait; the contrast make it interesting, and nice gray tones too; on the right side in the bottom of the image the arm which is visible is not clear if it belongs to the woman or to one of those hands and this, attracting attention, disturbs a bit
0 
