This Willie bus is a conceptual project designed by Tad Orlowski [1]. Note the design of the side elevations, which are made of transparent LCD screens.
Similar to #MiniArtBeat where Mini teamed up with creative agency KKLD to cover one of its cars with 48,000 LED bands [2], we really are starting to see Pixels Everywhere [3].
Not surprisingly this concept has gotten a lot of press (including Wired Magazine here [4]).