Microsoft Working on Zune HD?

When it comes to portable media players like Microsoft's Zune or Apple's iPod, we always find ourselves asking, "What could they possibly do next?" In Microsoft's case, the next "big thing" is possibly HD. Engadget recently posted some images from an apparent marketing campaign. One of the images clearly includes the new ZuneHD logo, and another gives us a glimpse at what the device looks like.