Need to update those old list to a new SmartArt diagram? Right-click anywhere in the bulleted list, point to Convert to SmartArt, and then click the diagram layout that you want to use. If you don’t see your preferred diagram layout, click More SmartArt Graphics to choose a layout from the Choose a SmartArt Graphic dialog box. After your list converts to a diagram, the SmartArt Tools Design and Format tabs appear when the diagram is active. Use those tabs to apply formatting or even change the diagram layout.
Thanks to Bridgette for pointing out that this does not work in Word.