The point of all this (and RTG, you said what I was thinking) is that there is no difference between HD and the main signal. If you're going to offer the same stuff on the HD channels that I'm going to find on the main channels, where's the draw? Add in all the technical problems surrounding HD radio, and there's even less chance that people will listen. Through no fault of their own, a lot simply can't!
The way I look at it, if HD radio content is so compelling as the apologists may argue, why not stream it through your internet portal? WiFi audio streaming is a reality, so there is even less reason (as if we needed less reason) to own an HD radio. Dump the technology altogether and focus on delivering fresh content where people can be found (i.e. - the mobile internet).
I agree, and the other big problem I have with HD Radio (beyond all of the technical failures) is that all of the ads and the marketing campaign keep talking about how HD Radio is free. Well, yes, the service is free, but you need to buy either an entirely new radio that's HD-ready or you have to buy an add-on to be able to get HD Radio signals and install it. Yes, you can get HD Radio on your iPod/iPhone... if you buy an $80 attachment that you now also have to carry around with you to listen. You can get HD Radio on your car radio... if you buy a new receiver that's HD-capable and, if it's not built-in like some of the JVC models, also buy the add-on and have the whole thing installed, which is another expense if you don't do it yourself.
I've said it before and I'll say it again: Fix the main signal and make that the best possible and most compelling outlet to compete with all the other media out there, then we can talk about those "stations between the stations."