One highlight: Wallace underlines the word problematize and notes, "This is a bullshit academic word. Shun it. Fly it. Trust me," a comment that wittily alludes to the final line of Suttree. In his later comments, Wallace at least twice uses the word problematize himself (though he puts scare quotes around it) to critique the student's own assertions.
Overall, I like the image of Wallace that comes through his comments. He seems like a decent human being with a good sense of humor, and I'm impressed that he gave such time and attention to this guy's paper—balancing criticism with lots of encouragement. He also balances grammatical corrections with commentary on the content of the paper.
In the end, Wallace pronounces the essay "Magnificent" and gives it an A+++. He then assigns a penalty for "syntax, grandiloquence" and knocks the grade down to an A+.