Finally,

I whished long for this, now it happened:

Shutterstock implemented a function that shows the keywords that led to a download for each image.

You find the function in the new "Image Gallery Stats" in their "Shutterstock Darkroom".

I wrote a blog post about it in German:
http://www.alltageinesfotoproduzenten.de/2011/04/28/shutterstock-verraet-endlich-die-suchbegriffe-der-bildkaeufer/

Here is the automated english Google translation:
http://translate.google.com/translate?hl=de&sl=auto&tl=en&u=http://www.alltageinesfotoproduzenten.de/2011/04/28/shutterstock-verraet-endlich-die-suchbegriffe-der-bildkaeufer/&twu=1

What do you think of the function? Any helpful observations made?