What Microsoft UI technology was used to create Zune Media player (marketplace software, not device os)?

Question

UI looks like it could me made with silverlight, but it's not a web app.

Answer 1

If it is not a web app but looks like Silverlight, that it's WPF.

There are 3 types of applications which use XAML/WPF, an ordinary desktop WPF application, a WPF browser application and Silverlight in-browser application. In three cases, WPF is the technology used for UI.

I don't know what Zune Media Player uses exactly (desktop app, WPF browser app or Silverlight), but for sure, it looks like XAML/WPF.