Part of the joke is context. Sikoryak is best known for adapting classic literature using well known comic book characters that prove strangely appropriate. In this case, the statement would appear to be that iTunes has replaced the classics in this generation. Everyone used to know Dostoyevski. Now everyone knows Steve Jobs.

There's also the joke that iTunes spends tons of time and energy writing and revising this thing that absolutely no one ever reads, so attempting to elevate to the level of art a piece of writing that is, essentially, utterly meaningless and without value to everyone who encounters it, is quite funny.