The Regent in Hong Kong is fabulous on that harbor, but it's only got a small piece of land. And what's so magic about the Place Vendome anyway? The monument to Napoleon is too skinny-I don't like the proportions. Architecture, materials, technology are all way beyond that now. Cesar Ritz opened the Ritz in Paris in 1898. This is not just flapjawed developerspeak. Suppose somebody built the greatest hotel of all time-of any century on any continent. Suppose somebody built a hotel in Las Vegas that was the best hotel in the world, the best hotel that had ever been built. Touring one of the most expensive hotels ever constructed, BOB COLACELLO takes the measure of its builder, whose father was a compulsive gambler, whose friends include Rupert Murdoch, Ronald Perelman, and former president George Bush, and whose dreams are his blueprint for action Casino mogul Steve Wynn already owns three Las Vegas hotels-the Mirage, Treasure Island, and the Golden Nugget-but his heart is in his fourth, the 3,025-room, six-million-square-foot, $1.6 billion Bellagio, opening this month, which houses a $300 million art collection, an 1,800-seat theater, a host of luxury businesses such as Tiffany, Chanel, Armani, and Petrossian, and nine V.I.E villas, each with a personal spa.