The team writes: It is an audiovisual composition that is based on a single set of MIDI notes. Those notes influence both music and graphics at the same time. We did not take the usual route of creating a piece of music first and then find some visualization for it; instead both elements have been developed at the same time. When we decided to change something with the graphics, the changes immediately influenced the music as well.
See also their first iPhone App: iScraper