Back when the transition to ATSC was first detailed the FCC (if I
> recall correctly) stated that each licensee would be required to
> provide one stream of free programming in a resolution no less than
> that of its previous analog broadcast. Beyond this, stations are free
> to use the remaining bandwidth for whatever they wish (including pay
> services). This troubled me at the time, but most people I talked to
> seemed to dismiss the issue.
> There have already been a couple of schemes to use part of the ATSC
> bandwidth for pay services, though I can't tell from the original
> article whether this is one of them or whether they are talking about
> analog broadcasts. Regardless, I expect we will see a lot more of
> this as ATSC becomes more ubiquitous (and independent of whether
> analog broadcasts are discontinued).
Yep -- tis already spreading. This is an older article, but AFAIK US Digital is still going strong:
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