Emerging radio technologies are poised to attract serious buy-in by 2012, according to a recent projection by Dallas-based Parks Associates. The researcher projected a total of 70 million subscribers in the United States over the next five years, up from an estimated 24.7 million in 2008. At present, satellite radio has more than 20 million subscribers, while HD - or digital - radio has attracted roughly 4 million. (Digital Music News)