We just got back from the World on 12/7 and without a doubt everyone agreed that Artist's Point at the Wilderness Lodge was the best meal we had on the trip, which included Le Cellier, Rose & Crown, Prime Time Cafe, and Boma. So to actually respond to the question:
Artist's Point
Prime Time Cafe
Rose & Crown
For casual eating, the Flame Tree BBQ in the Animal Kingdom is great, particularly for the terraced table area.