Zune HD UI Makes a Peek at a Newer Windows Phone 7 Series Build?

It's uncertain if the new mockup of Windows Phone 7 Series that was posted on Charlie Kindel's Microsoft blog is a newer build or an older build of Windows Phone 7 Series, but the new shot does show that Windows Phone 7 Series and the Zune HD UI are closely related. The new mockup does not have the clean look that we've seen at Mobile World Congress, but for those that are complaining that Windows Phone 7 Series has a lot of wasted space on the main screen--particularly the black areas at the right edge and the bottom--the new mockup show that Windows Phone 7 Series make better use of available screen real estate, for better or worse.