Our pals over at Droxy informed us that BMW will be offering an optional HD Radio Tuner in the 2006 7-series. HD Radios are a relatively unknown evolution of terrestrial radio broadcasting. Think digital radio and you're pretty close to the concept. At this time, the aftermarket is the only place to get an HD radio. BMW is apparently the first manufacturer to offer it as an option.
While we are not experts on HD radio, we feel it is an attempt to update terrestrial radio to compete with satellite. We can't help but think that the downside of terrestrial radio is range and the limited content. However, I'd rather sport my pack of homemade MP3-CDs anyway.