Combine all ingredients except optional ingredients in a blender, and blend on high speed until mixed thoroughly. Refrigerate in a covered container for at least a few hours to allow the nog to thicken.
If you like, before serving, top each glass off with whipped topping and a sprinkling of cinnamon. Yum time!
If you want to make an alcoholic version, nix the rum extract and reduce the soymilk to 4 1/2 cups -- then add 5 ounces of rum to the recipe. Just tack on an additional 58 calories each serving.