Pandora is a company that mainly makes its money through advertising deals on its streaming Internet radio service. But a growing portion of the business is also affiliate downloads of songs that users hear on Pandora and want to buy on either iTunes or Amazon’s MP3 service. And the biggest mover accelerating growth in that regard are downloads taking place on the iPhone. Users are buying about a million songs a month now from these affiliate links on Pandora, CTO Tom Conrad tells me. Of those, a solid 20% are coming directly from Pandora’s iPhone app, which includes an easy link to open the iPhone’s iTunes app, and buy a track. That’s really impressive considering that it’s just one phone that a relatively small percentage of their users use. Read more at www.techcrunch.com