I don't know why all the negative comments about Pierce's singing - he sings a heck of a lot better than a lot of amateurs I know, and certainly a lot better than half the contestants on American Idol. And he didn't go flat at any time.
As for the movie itself - loved it! Sat through the entire thing with a smile on my face and am glad I sat through the credits for the final number with the entire cast. This is a movie I would buy to watch again.