I suggest visiting
Satellite Guys Website to research this. It's the Pelican of the satellite TV world.
Right now, Dish Network has more HD programming than Directv. Directv has promised a lot for the coming year though, so we'll have to see how that pans out.
In my area, my cable choice is Time Warner and they suck, don't even OFFER HD. Dish Network has been good for me, except in the rare electrical storm.