This was announced recently at maritime matters site:
WESTERDAM to replace aging RIVIERA
May 7: Further to the 29 March posting regarding the transfer of WESTERDAM from Holland America to Costa in June of 2002, it was announced that the 30,400 gt COSTA RIVIERA (originally Lloyd Triestino's GUGLIEMO MARCONI) will be removed from the Costa fleet. The 1963-built vessel remains in service but is currently for sale.
It is with sadness we learn of the retirement of the Marconi. This was the sleek Italian liner that my wife and i first saw each other. It was at the captains cocktail party that the two of us first saw each other. The many happy thoughts and excitement that the all Italian officers and all Italian dinning staff offered aboard this Italian built beauty of a ship. Yes we have pictures of this raked bow vessel and remember how she "cut" through the ocean at 27 knots. Sailing the Marconi in her time was truly a trip to Italy....In my wifes heart and mine, no ship will ever have the special feeling of Italy and being an honored passenger aboard a "real" Italian cruise liner.