Apple's widely anticipated Sandy Bridge-equipped iMacs should not only be unveiled on May 3 but would be ready to sell in stores the same day, tipsters maintained Saturday. The all-in-ones would not only be unveiled early Tuesday but see Apple retail staff perform a "visual night," or an overnight rearranging of the store to put in new demo models and displays. The timing as cast by AppleInsider's sources would both help smooth out the launch and let buyers get the system the very same day.