A firmware update will bring two great features to the Zune HD in the second quarter of this year. The first is native XviD support, which is self-explanatory. The second requires just a tad more explanation.
The Smart DJ feature, now on the Zune's PC software, will make its way to the HD, offering on the fly track suggestions. That's OK - pretty similar to the iPod's Genius features - but what will make the feature great is that Smart DJ will also work over the Zune HD's Wi-Fi connection, allowing you to stream these suggested tracks from the cloud (instead of needing to have all that suggested music stored on the device already).