Whatever he has been listening to and has something to say about. Some of these are a paragraph, some run long. Half of Why I Hate This Album. Writes here when he has something to say that won't fit in an episode, which is most weeks.
It is four chords and a chant and it absolutely works, which I resent. The Bruno Mars verse is doing more structural work than anyone gives it credit for. I have heard it in three shops this week and did not once want it to stop.