I live in Buffalo, NY. All the network stations, NBC, CBS, Fox, CW, and PBS all broadcast a digital signal. The local stations themselves don't broadcast local programing, like the news, in HD, but all the network HD is being broadcasted in HD.
I had to get an OTA antenna to get my local HD channels because I gave up waiting for last years promised HD locals from Dish.
I talked to an engineer at one of the local stations, last fall, and he said that if Dish wanted their HD signal, all they had to do is uplink it, and throw the switch.
Now, if they have they are having a problem getting the rights to rebroadcast their HD siginal, that's another story.