Woah, I love that, gotta give it a try

Yes it is! The theme is called Reactionary Plus.

Yep, it’s Dolphin with the Reactionary Plus theme

It’s Audacious, an open source media player which can actually use Winamp skins directly. It’s awesome, I love it. Give it a shot if you’d like, you can get it for Windows, Linux and Mac, and you can use any of the skins from the Winamp Skin Museum.