Today, Microsoft sent the updated Zune firmware HD 4.5, this update Smart DJ lets you play the instrument. Smart DJ selects songs from your collection that are similar to the artist or song you choose. The update also allows for more file support for the device, like .AVI and XVID without a conversion.  In addition, the browser is faster. I was able to load zUnited in seconds. In addition, the update takes pictures of an artist so that when in the Now Playing screen.

Full changes:
This is not official until Microsoft sends then feel free to comment if we missed something!

- Smart DJ
- Native AVI and XVID support
- Marketplace on TV-Out
- Picks on-device
- Artist view and now playing feature multiple artist background pictures, rather than just one, now.
- Increase the overall performance. Miniature animations load faster and smoother.
- Faster, better browser. web pages larger than before would crash the browser now loads, you can zoom in on images without blurring, and press to zoom works better.
- You can now sort bookmarks by date added or alphabetically.
- You can change the name of browser bookmarks. Press and hold one of the favorites, and then click Rename.
- You can save pictures of a webpage to your device. Press and hold on any non-link part of a webpage to do so. You can do the same for individual images!
- It now warns you that deleting your browser history takes forever.
- In artist view, you can now play all albums or songs, or add them to now playing.
- In the marketplace, you can see more than 3 of an artist’s top songs.
- Playlists now have a transparent background in Quickplay.
- You can now connect to wireless networks that don’t broadcast an SSID. They show up as “hidden network” on the device.
- Games no longer have ads in front of them.

Also, if you have any problems with Smart DJ Miss does not work, leave your device connected via USB, the Zune software was, for one hour. The situation must be resolved.