At approximately 4 minutes per song (Apple's average), we can play through 150 songs in 10 hours (far less than the 1000 song storage capacity), giving us approximately 1.09•10²⁰ electrons used per song.

That's downright efficient compared to the piggish 160 gig iPod Classic, which weighs in at 850mA•h, 40h: 1.27•10²¹ e / song.