According to new images published by Engadget, Microsoft is preparing a third-generation Zune device, presently titled Zune HD. One of the images includes a direct look at the potential device, which appears to have a wide-aspect touchscreen and an Apple-like black and silver exterior, with the rest showing abstract illustrations. Microsoft has previously targeted both the iPod classic and iPod nano with its drive- and flash-based Zunes, respectively,…