MARY EWING-MULLIGAN, Master of Wine, and ED McCARTHY are among the best-known, most widely respected wine experts in the United States. They are coauthors of the bestselling Wine For Dummies and six other wine books, and each is a wine columnist and frequent contributor to magazines, radio, and television. Mary, the first female Master of Wine in the U.S., is president of International Wine Center, a New York City school that trains hundreds of wine professionals and wine lovers each year. Ed is generally considered the leading U.S. expert on Champagne.