The official position is that not all units are affected, and those that are affected are handled on a case-by-case basis. This forum represents a worldwide audience, and thousands and thousands of units are in homes with little or no issue.
I can't say if you'll hear it, but if you do, make sure you've purchased from a reputable dealer so that you can do what's best for you. Just a piece of unofficial, friendly advice.
My research as found many buyers of this tv complaining about a loud buzzing sound. As one who was very close to buying this unit, does Samsung have an official position about this alleged defect? Has it been identified and corrected on new units?