Previewed at WWDC, launching in the fall.
Apple No Longer Accepting App Store Reviews for Redeemed Promo Codes
As noted in the forums at our sister site Touch Arcade, Apple has apparently made a change to its App Store app review policies, no longer permitting users who have obtained applications via promo code to leave reviews for them.
According to Apple representatives, the change has been made in order to help prevent developers from gaming the ratings and reviews system by using an entire batch of promo codes to boost their profile.
I worked with Apple to resolve this issue and they have responded that "it is no longer possible to rate or review an app if it was downloaded using a developer's promotional code to prevent comprimising [sic] of the rating system".Another developer who had been running a Promo Dispenser service for connecting developers offering promo codes with users willing to provide reviews in exchange for them reports that users are receiving a standard response from Apple about the change when inquiring about difficulties leaving reviews.
Anand here again from iTunes Store Customer Support. Thanks for writing back and letting me know your concern. I understand that you are still not able to write a review. I know how disappointing it can be when things don't work out the way they should. I am sorry to inform that it is no longer possible to rate or review an app if it was downloaded using a developer's promotional code.
However, I took the liberty of submitting your feedback to Apple on your behalf. Please know that Apple takes the feedback from our customers very seriously. This is the reason for our feedback page - to create a forum where our users can vent, praise or share whatever feelings they have to allow us to meet your needs, and grow as a company. I suggest that you use the link in order to share your feedback with us. I would also encourage you to share this link with all of your friends and family who wish to submit the feedback, and have them all submit the same request.