If you are generally offended by Southpark or Team America, or had no desire to see them, then I would imagine you won't like this either. But since it has the same creators shouldn't that be obvious????
There is a lot here for people who are more Broadway then Southpark fans too though, especially all the little homages to other musicals throughout (Wicked progressions in 'you and me', 'Hasa Diga' - Lion King, and 'I Believe' parodies Sound of Music.) About 1/2 the soundtrack is highly addictive and will stick in your head - careful singing some of those lyrics in public though! The rest is enjoyable, but the highlights for me are the first five songs and I Believe.
You also have to have a sense of humor about religion in general to appreciate the musical, but I can say as a rather liberal Christian I didn't find it offensive - but you need to have an open mind and also realize there is in-show context to the songs that makes the overall message less offensive then the straight lyrics. Overall, especially having seen the actual show, the show is quite good-hearted about religion and although it pokes fun at Mormonism I didn't find it to be mean spirited.
For the one star reviewers(particularly on itunes)... why are you seeking out something you are predisposed to find offensive? If you don't like it.... Turn it off, like a light switch... or put it in a box and CRUSH IT! ;)