Calling my customers? I usually hang up right away for these spam calls... it doesn't seem like the best idea to annoy my customers with any calls like this.
This seems like a good idea for being able to poll customers in a somewhat anonymous, yet personalized, way to gather better feedback than what you'd get if you just sent an email with "Now that your project is complete, are you satisfied with out services?"
I don't have a large enough clientele to take advantage, but I certainly see the usefulness of it.