Don't worry, DRM won't replace AM on shortwave any time soon - if ever.
Whoever wants DRM to become the new standard will have to have a very
long breath, 20-30 years for sure. In many poorer regions of the world
it's likely to be even longer - I don't see how, say, someone in India
who can barely afford a used ICF-7600DS can be offered any half decent
DRM radio any time soon. (Actually I'd give WorldSpace greater chances
of succeeding.) For the really poor regions, there's another problem -
servicing. Simple analog radios are usually not hard to repair, but if
some once-hypermodern-and-now-out-of-production IC fails, good luck
finding a replacement [1]; soldering and unsoldering of SMD stuff isn't
easy either.

DAB, BTW, is more of an FM replacement. Still has plenty of startup
problems here, in spite of having been introduced years ago. Time will
tell whether it'll become the new standard for "local" listening.

Stephan

[1] That reminds me of a story I once read - someone goes into an
electronics store and buys some tubes for his 40 year old radio, which
baffles another customer who needs an IC for his rather recent TV - this
is out of production already.
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