I'm not even a "stan" of Mariah--just a big fan--but to me it's easy to see what's live and what isn't.
This is roughly half live. The verses are live, the choruses are not. The belting is but the whistles are not. I liked the performance though. I just wonder why it's so difficult for her to stay on key all the time. I always cringe when she's about to hit a tough note.