I wouldn't be too concerned about the amount of SD in the Countdown show. It seemed heavily SD yesterday, as well. I mentioned yesterday, but it bears repeating:
One thing to remember: RF HD cameras are not yet available. Nascar coverage depends heavily on RF cameras not only for all the in-car coverage, but also virtually all of their handheld and pit coverage. Assume going in that anything without cable is going to be an SD native feed.
At least they've got 16x9 blocks in their SD cameras so they're not zooming the image to get 16x9. Also, when you see the in-car, you'll see pillars as those cameras are 4x3, and again, they chose not to zoom.