Today NVIDIA officially announced that their Tegra chip is inside the Zune HD. A thing we already know actually.
"Tegra provides the multimedia muscle in Zune HD," said Michael Rayfield, general manager of NVIDIA’s mobile business. "Users will love the device’s new design, amazing multimedia features and HD video out capability. Zune HD is a must-have for anyone looking for the best portable digital media player on the market."

Key to Tegra’s rich multimedia features are eight independent processors, each designed for a specific class of tasks - among them are an HD video processor, an audio processor, a graphics processor, and two ARM cores.

NVIDIA says that there are 50 active Tegra processor-based design projects currently in the works today.

The Microsoft Zune HD offers a multi-touch navigation on a 3.3 inch 16:9 OLED touchscreen display with 480x272px resolution. The new Zune HD supports multi-touch navigation like the Apple iPod touch.
Other feature highlights of the Microsoft Zune HD include integrated HD Radio receiver, HD video out support 720p HD movies (requires Zune HD & AV Dock), Wi-Fi, built-in accelerometer, web browser, and touchscreen QWERTY keyboard.

The Zune HD is available for pre-order on Amazon and will ship September 15th.