Over 60 million Americans listen to some form of internet radio in a typical week

"Just over 60 million Americans listen to some form of Internet radio in a typical week. This includes both AM/FM simulcast streams and Internet-only radio (e.g. Pandora, AccuRadio).
84% of this group regularly listens for at least five minutes to AM/FM simulcast streams in a typical week.
62% of the total streaming group regularly listens for at least five minutes listening to Internet-only streams."
Source: Press release from Bridge Ratings, 2nd February 2010