First things first: It gives you an e-mail address to enter. You read it. It did not exclude readers from entering. It did not require more than you send an e-mail to enter.
Second: This recording is incredible.
Third: It is NOT a "soundtrack". A "soundtrack" is a recording from a film or video...music that was created/arranged/conducted/added to the video or film. It is a new recording, conducted brilliantly by John Wilson, and sung to perfection by a stunning cast.
I believe Oklahoma was the first Original Broadway Cast Recording, that set the precedent for all those after. Something to do with a dispute between record labels and the unions then, and the unions wouldn't allow the record label artists to record the songs as heard in the show. So some bright spark at one of the labels had the idea to get around that restriction by getting the cast to record it themselves. Or something along those lines.
I've heard a few of the tracks from this recording as Aedin Gormley played some on her RTE Lyric FM show recently. It does indeed sound very impressive.