Even with all the music download services floating between Verizon Wireless, Sprint Nextel and others, wireless subs just aren't downloading music very much. Only about two percent of US customers download music to their handsets over the air according to Jupiter Research. Not an OTA fan? Chew on this: only five percent of music-capable handsets get music sideloaded from nearby PCs as well. 28 million US customers will have music-capable handsets at the end of this year, while a minimal percentage will actually use that capability. Will it get better with the iPhone being sold in volume this year? We'll see.