HDTV broadcasts on a UHF frequency. Chances are that you will be able to pick up over the air broadcasts on the channels new frequency. If you don't know what your local stations new frequencies are you can call the station and ask them.
Sometime in the near future the VHF channels (2-13) will quit broadcasting in their entirety and the channels will revert back to the FCC. What they are going to do with the frequencies then I don't know.
Chad