Well, ok. Hips wider than shoulders is rare, but hips as wide as shoulders is common.
The widest point on the hips occurs at the top of the thighs, going across the groin. In the linked picture the widest point of the shoulders is wider than the widest of the hips, but not by much. I think it would be less than 1 pixel at the size you're using.
Ref 1:
http://fineart.sk/show.php?w=1367 (large image, nude)
Your reference pic:

Difficult to measure accurately because of the twist in the pose and the hair, but she has a slightly more hourglass figure than the woman in the ref pic I linked above.
I measure about 72 pixels across the shoulders (maybe as high as 75 pixels), 63 at the top of the hips, and 72 again at the bottom of the hips (maybe as low as 70).
At what should be the widest point is roughly 40 pixels from edge to centerline, so maybe as high as 79 or so at the widest point, but this has a lot of error in the measure.
So yeah, hips = shoulders in width is a good rule of thumb for women.
Also, your reference pic has her hip further to the right than her shoulder (blue line), while you've got the hip far to the inside of the shoulder. How closely do you want to match the reference pose?
Tourist