Here's a few sample visualizations. The gist of it is that these display how frequently each artist, album, or track is played over time. New artists/albums/tracks are added to the edges.

Track-based graph

Artist-based graph

Album-based graph -- this guys has quite the variety

Artist-based graph -- with random coloring.

Artist-based graph -- without smoothing. (An early version of the script, but still an option to create)