According to this piece in Engadget, Microsoft plants to end its Zune platform.
It appears Microsoft will not be putting out any new hardware in the line, and will be henceforward focusing on integrating Zune functionality with the Windows Phone 7 platform. I guess this is a smart move at this point. The Zune HD is actually a great device, it's a shame Microsoft didn't promote it at all.
I would recommend gettig one as soon as possible. The sound is great and the HD radio stations come in handy.