Rock radio consultants Jacobs Media report that Howard Stern's move has helped SIRIUS match and surpass the subscriber rate of XM among Rock radio listeners. The report adds that approximately 70% of Stern's listeners acknowledge they've stayed with commercial radio morning shows. Jacobs Media makes the statement that the biggest winners appear to be many of Stern's former FM competitors.
One very very important thing to point out, Jacobs Media is contracted by major FM broadcast companies.. According to JacobsMedia.com in the about us part: "Jacobs Media services are used by nearly every major broadcasting company, including Infinity (now CBS Radio), Entercom, Emmis, ABC, Cox, Saga, Citadel, Journal, Susquehanna, and others."
The survey was conducted in late February, roughly 5-6 weeks after Stern's debut on SIRIUS.
Read the report here with some nice little charts and graphs