So which is the higher resolution?
720P is 720P...it either is or isn't....DirecTv broadcasts in 1080i
Cable and satellite compress the signal many many times more than OTA.
not true...I can see the difference between the local OTA HD feed and the same feed through DirecTV
The resolution has nothing to do with the compression. Cable and satellite companies sacrifice bit rate to allow for more channels on their available bandwidth.
Under normal circumstances compression can be made to be pretty much unnoticeable, but the cable/satellite companies have to do it on the fly so their picture quality does suffer for it.