Daniel Hall has "two beliefs about pop culture that initially sound incompatible":
1. There will never again be a musical act that attains the popularity and cultural permeation of the Beatles.
2. It is nigh inevitable that a book or book series will one day achieve or surpass the popularity and cultural permeation of Harry Potter.
Daniel goes on to explain that the music industry is becoming ever more niche-y (is that a word?) while book retailing is getting "spikier". But I’m not sure: the long tail of books is just as long as the long tail of music, while the selection of CDs at Walmart is not much greater than the selection of books at Walmart.
I would point out that the popularity and cultural permeation of the Beatles is at least one and quite possibly two orders of magnitude greater than the popularity and cultural permeation of Harry Potter, so it’s quite possible for a book series to surpass Harry Potter while coming nowhere near to Beatles levels.
Alternatively, I could point out that there’s a long-running book series which outsells Harry Potter every year and has at least an order of magnitude more popularity and cultural permeation than even the Beatles: it’s called the Bible, and if you don’t believe it’s a pop-cultural phenomenon, I’d just point you here. Staying within the secular world, there’s another series with more popularity and cultural permeation than Harry Potter: the collected works of William Shakespeare.
Cultural permeation is something which tends to grow over time, at least for the tiny minority of cultural artifacts which don’t die out entirely. It’s partly a function of remix culture: in terms of cultural permeation per second of music, you probably couldn’t beat the amen break, which continues to grow in cultural importance over time. But even before remix culture time does amazing things to cultural importance: that’s why Holden Caulfield still probably has more resonance than Harry Potter.
But stick with units sold per year. Yes, it’s almost certainly true that no musical artist will ever achieve Beatles proportions again, while it’s conceivable that a book author will outsell Harry Potter. I think the reason is that the Beatles went global back in the 1960s, because it’s easy for music to do that. Books have only much more recently started going global; the phenomenon of the global book has yet to reach its peak.
Incidentally, I’m super happy to see bylined blog entries over at Free Exchange. Now that they’ve been allowed for guest contributors, could we please have them for the regular contributors as well?