A new survey by Rock radio consultants Jacobs Media found that iPod ownership has risen sharply among radio listeners. The firm said that the percentage of iPod owners has increased from 21% in its 2005 study to 35% in 2006, and that nearly half (48%) of those who haven’t purchased an iPod or MP3 player say they are very or somewhat likely to soon. Unsurprisingly, Jacobs also said that iPods are eating into radio listening. “There are strong indicators that at least initially, iPods sharply cut into time spent listening to radio,” the firm said. “About one-fifth of iPod owners say they listen mostly or exclusively to these devices. Four in ten now split their listening between iPods and radio, while over one-third primarily listen to the radio.” In addition, Jacobs said that one-fifth (22%) of those who own an iPod say they’ve downloaded a podcast. Of this group, nearly two-thirds (64%) subscribe to at least one podcast.