Las Vegas was the place to be Tuesday night as newly-shorn diva Celine Dion debuted her much-hyped $30 million stage show "A New Day" at the 4,100-seat Colosseum at Caesar's Palace. During the 100-minute extravaganza, the 35-year-old singer belted out 20 tunes, including such classics as "Fever," "At Last" and "I've Got the World on a String." Under the terms of her contract, Dion is expected perform five nights a week, 40 weeks a year until 2006 — or until the locals stage an uprising against her.