Apple on Tuesday announced upgrades to its iMac line, including Retina displays and Intel sixth-gen Skylake processors. The company also reached deeper into its hat to pull out "magical" new peripherals. The entire 27-inch series of iMacs now come with the 5K Retina displays, while the 21.5 inch iMac comes with a 4K Retina display. There are about 5.3 million more pixels to be had in a 5K display.