...That entire UI needs to become the new Modern/Metro UI for Windows 10. 34 seconds into the video is just an amazing overall UI. I like the UI as it is now, but this is just better. This makes excellent use of font size while still keeping the "slide left or right" aspect of the UI.
Anyway, who needs the XBM team to adopt this UI? All we need is permission to use this, and a good developer (or two), and we could have a great replacement music player app on our hands (or should I say, phones).