Update: The update is now available to download for Xbox 360 Kinect. It's an automatic update that's 34 MB in size.
The Elder Scrolls V: Skyrim Xbox 360 owners with Kinect can soon begin dragon shouting their way to victory.
The update for Kinect support with English voice commands goes live tomorrow, May 1. Bethesda says French, Italian, German, and Spanish versions are all in final testing and dates for those versions will be revealed later.
Bethesda also posted a list of all the Kinect voice commands, which you can read here (PDF).
Regarding the first piece of download content for the game, Bethesda also teased that new information will be revealed tomorrow.