In what's being called a win-win situation, the Federal Communications Commission unanimously approved a standard for digital radio today, meaning the first real advances for the medium in years are just around the corner.

The FCC approved technology created by iBiquity Digital Corp., a privately held company that counts Viacom(NYSE: VIA), Disney's(NYSE: DIS) ABC, Clear Channel Communications(NYSE: CCU), and Cox Communications(NYSE: COX) as investors. As a result, stations are expected to begin broadcasting digital signals in the next several months.

What will this mean for you? For starters, you can expect CD-quality sound through your radio's speakers once digital receivers hit the market. (You'll still be able to listen to digital stations with your current equipment, however.) But there will be other benefits, too. Because the digital signal can piggyback on the normal analog signal, it can send separate information through the two channels. That means customers could get programs on demand to listen or record for a later time. The alternate signal could also send other types of information, such as pictures, news, and artist information.

It's worth considering what effect the new technology will eventually have on XM Satellite Radio(Nasdaq: XMSR) and Sirius Satellite Radio(Nasdaq: SIRI). One of their major selling points (besides being able to listen to a single station coast to coast) is the digital-quality sound. Once that's offered for free, however, the two companies -- if they even survive -- may see a drop-off in the number of subscribers willing to pay $10 or more per month.