Re: Then there is Radio 5
I think power of receivers is the only argument against the change.
The switch from analogue to digital TV has gone smoothly and, if my mum is anything to go by, people are generally happy with the result (time-shifting has become easier). The same would be true for radio. Of course, people would complain but then they always do.
AM does propagate further and require less power to receive than FM or DAB. Partly because of that there is more money in FM because it allows for a better carve up of the audience (radio is often very local) but there are limits on the number of stations that can run nationwide for the few stations that don't have identikit programming.
Anyway, FM propagation has its own problems: reception of the German version of Radio 4 varies from dreadful to shitty in my flat; it's not on LW and MW receivers are almost non-existent do DAB really is the only choice. I never listen to any of the other stations but then I never watch any of the hundreds of TV channels that are available either (more of the same old shit just at different times and in different languages).
As a society we have embraced digital broadcasting. DAB, or at least DAB+, is a good solution for radio. I suspect that, er, reception would improve if say mobile phones started supporting it instead of / as well as FM so that we could listen to it on speakerphone without having to plug a headset in.
The alternative, of course, given the popularity of radio of DVB-T might simply to extend that.