6Fg8 has created Power Radio. Her introduction says everything you'll need to know:

Why PowerRadio?

The built-im FM player - at least on HTC HD - misses many features i'd like to have in a FM radio. PowerRadio delivers many data available via RDS which would otherwise be invisible to the listener. Here are just a few examples:

• Radiotext: contains information broadcast by the respective station. What you get here totally depens on the broadcaster. You might see title and interpret, call-in numbers, SMS trafficservice numbers, URL's etc.
• Traffic announcements, program type, coverage area, date, time, timezone, various status flags

Continue on to the application thread.