If you were already developing games for your Zune using XNA Game Studio, you’ll be happy to know that moving that game over to the new Zune HD will be remarkably easy. Today we’ve released the XNA Game Studio 3.1 Zune HD Extensions that will allow you to deploy to your new device and includes a few new API’s as well.
There is also a thread on the XNA Creators Club forums for any questions or discussions.