Combine apricot nectar, apricots, and cherries or cranberries in a small saucepan; bring to boiling. Remove from heat and let stand 5 minutes. Drain fruit, reserving liquid.
Meanwhile, preheat oven to 350 degrees F. Core whole pears almost through to bottom. Place pears in a 2-quart square baking dish. Combine drained fruit mixture, sugar, and nutmeg. Spoon into center of each pear. Combine reserved liquid, cardamom, and vanilla; pour over and around pears.
Bake, covered, in preheated oven for 20 minutes. Uncover; bake 20 to 25 minutes more or until pears are tender, basting occasionally with cooking liquid.
To serve, spoon liquid over pears. Serve warm, dolloped with reduced-fat yogurt or sour cream and sprinkled with nutmeg, if desired. Makes 4 servings.