So I have a base 2010 and actually like the factory radio from Honda. I noticed that the stations here who offer HD digital signals, show HD in the display name on the base Fit headunit. Does the stereo actually receive a HD signal or do all the stations just add HD in there call name. One can dream right?

 

HD radio isn't high definition. It's hybrid digital. And no, the Fit's radio doesn't process these signals. Also the fidelity of HD radio isn't any better than regular FM and is probably worse in spite of what they may advertise.

They're transmitted with the normal FM signal in the extra bandwidth available and are a secondary "channel" for the radio station. It allows the radio stations to broadcast multiple streams and they only have to pay for one license. I don't know if they are catching on. I suspect they aren't.

I think HD radio is going to go the way of stereo AM that enjoyed brief life in the 80s.

I might be wrong but it seems the quality, the bit rate of the signal is left up to the station. wiki link.