Same thing happened to me yesterday. After reading the articles about the LG screen issues, I made an appointment. Mine wasn't too bad, but still somewhate distracting watching movies.
The Genius rep said my issue was "very minor" but agreed to replace. However they would only do this once. If the replacement was not good enough I just had to return for refund.
We tried to verify in store if the new one was better, but really impossible 'cause no dark room there.
Anyway, took it home and it is "much" better, though still not quite as good as iPad 1. Nevertheless, I am satisfied and frankly I hate the waste involved in changing out all that hardware for just this one relatively minor issue.
Happy now. Great product overall...