I'd be interested in learning how they implemented the UI - it looks like it's native to Windows 8 but runs just as well on Windows 7. Would be interested to hear what toolkit they used.
So far, the UX has been impressive for a tool that has historically not run very well on Windows.
Edit: They've mentioned the toolkits used at the bottom of the page. Apparently this is written in C#.
Edit: They've mentioned the toolkits used at the bottom of the page. Apparently this is written in C#.