Speaking of music critics at the New Yorker... Jason Kottke has a really good interview with Alex Ross, discussing Ross's new book The Rest Is Noise, on instrumental music in the twentieth century.
I'm picking the phrase "instrumental music" out of thin air, because Ross argues that there is no single tradition of composition that we can call "classical music":
My big thing is that classical music doesn't really exist. When you have a repertory that goes from Hildegard von Bingen's medieval chant to Vivaldi's bustling Baroque concertos to Wagner's five-hour music dramas to John Cage's chance-produced electronic noise to Steve Reich's West African-influenced "Drumming," you're not talking about a single sound. Whatever variety of noise you desire, we've got it at the classical emporium. I'd suggest plunging it at various ends of the spectrum - some Vivaldi or Bach, the Beethoven "Eroica" or some other big-shouldered nineteenth-century classic, Stravinsky's "Rite of Spring" (which foreshadows so much pop music to come), and Reich or Philip Glass. The idea is to get a feeling for what composers were trying to express at any given time, and, of course, deciding whether you want to follow them. There's no correct path through the labyrinth.
As that quote suggests, Ross has some sage advice for people like Kottke (and me), who are music-savvy but don't know very much about this section of the music store. He also has more multimedia stuff on his book blog. Well worth checking out.