Mariah Carey is the diva-est of the divas: when asked about her rival Jennifer Lopez, she falsely replied “I don’t know her,” a pose she maintains to this day. She’s also the queen of the carolers: 1994’s “All I Want for Christmas is You” is the 12th best-selling single of all time. Celebrating the re-release of her yuletide album, Carey performs at Madison Square Garden, an arena large enough for her unbelievably wide-ranging voice and her gleefully large ego. —C.J.F.