Sony shrunk down the PlayStation 4 Slim and the result is noticeable from the get go. It's thinner, has a slightly smaller footprint and does away with the ugly glossy plastic in favor of a sandpaper-ish exterior. The controller also gets a tweak with an LED light added above the touchpad and a slightly lighter color tone for the buttons.
Lastly, you'll note that the PlayStation logo is actually sideways, which is odd if you're laying the console down horizontally. But it does help you figure out the right way to position the PS4 if you plan on placing it upright.