Digital radio in the U.S.

I have found that satellite radio would not function in our apartment - the antenna needs to be on a windowsill, and the window must face south. Too bad.

Now, about digital radio. Most of the information I can find relates to the U.K. Here is what the iBiquity site says:

"Like its analog version, the Recepter Radio HD is in the mold of high-quality table radios made famous by the legendary Henry Kloss and his line of Tivoli receivers. But this radio has circuitry inside that not only receives regular AM and FM stations, but also the new digital versions of those stations.

The Recepter HD uses the digital broadcasting system created by iBiquity. It’s a system only approved in the United States. Other countries around the world (including Canada) use different digital radio broadcast technologies."

Does anyone know if those "different digital radio broadcast technologies" are available in the U.S., or does iBiquity have a total lock on digital broadcasting here?

Is the choice of station limited to the ordinary local ones, or does it cover a wider spectrum?

If anyone here (specifically in the U.S, obviously) has digital radio what do you think of it? Do the stations include classical music? Is the location of the unit a necessary consideration as with satellite radio?

Any and all information welcome.