After the first mp4 player from Cowon S9 with an AMOLED, Sonys NWZ-X-Serie now Microsoft bring out a new multimedia player with an OLED Display.

Engadget.com about the Zune HD OLED Display;

The OLED screen looks absolutely stunning -- even at severe viewing angles, colors were super bright, edges were crisp, and text looked beautiful.

Product Features Zune HD:

Touchscreen: Get quick and instant access to your content with multi-touch navigation. With a 3.3-inch screen and vivid 16:9 OLED display (480x272 resolution), premium entertainment is at your fingertips.1
HD Radio: Tune into your favorite stations with crystal-clear reception. With an integrated HD Radio receiver, you can access a variety of HD Radio stations at no additional cost. Plus, tag the songs you like for later purchase.

HD Video Out: Watch supported 720p HD films, TV shows, and videos in high definition on your HDTV through the Zune HD & AV Dock (sold separately). Or, take them with you for premium entertainment on the go. Additional dock and HDTV are required.
Wireless: Connect, update, and buy content wirelessly from Wi-Fi hot spots. Stream millions of songs over Wi-Fi directly to your Zune HD and turn it into a portable digital jukebox.
Web Browser: Surf the web anywhere you have a Wi-Fi connection. Enjoy your favorite websites with a full-featured web browser, including tap-to-zoom technology, built-in accelerometer, and touchscreen QWERTY keyboard.
Zune on Xbox LIVE: Starting this fall, a broad selection of films and TV shows from Zune video on Xbox 360 will be available to start and stream instantly, in the highest video quality (1080p) and at the push of a button.2 No discs, no waiting for downloads and no delays. Get the selection of a video megastore, the best video clarity available and the convenience of on-demand, only on Xbox 360.

Zune HD Pre-Order at Amazon