According to www.airlinersonline.com:
"Virgin Atlantic Airways (London) is considering canceling their eight options for the new Airbus A340-600 (they hold ten firm orders with both G-VSHY, msn 383 and G-VMEG, msn 391 due in June 2002) in favor of supporting the proposed Boeing 777-300"
773 will look great in Virgin's colours. But why to buy the most expensive aircraft , when they have a cheaper and similar Airbus version? Good luck anyways!