SIGH OF THE TIMES: I.B. Bad’s latest column was written a day before the death of Steve Jobs, but the imprint of the Apple auteur is, of course, omnipresent in every aspect of the modern music business, which is I.B.’s beat, hence the nod to Mumford & Sons surpassing 1 million paid album downloads, the vast majority of them purchased at the iTunes Store. Some of those who figure prominently in the column express their feelings about this transformative figure immediately below. (10/7p)