Dish is likely to have a solution, probably based on the new Slingbox Pro HD technology and something like the Slingcatcher. Or maybe they could do something QAM based. But I don't think we will ever see true ATSC modulation on a Dish box.
Dish needs a solution for this pronto. Not only are many households getting multiple HDTVs, but (if it hasn't happened already), SDTVs may lack NTSC tuners, messing up the TV2 functionality for SDTVs