Cory Doctorow has written a spot-on new column over at Information Week on how Apple iTunes' DRM is bad for business (not just customers). It's a great overview of the problems associated with DRM, in language that is fairly accessible. What's interesting is his tone, though, which seems to target big record companies -- laying out for them how their insistence on DRM is shooting them in the foot, putting them at Apple's beck and call.