I had sent an email to the Engineering team at the WLS-7 Chicago, asking about technical issues which might have caused them to air it in 4:3 SD (and whether this problem might be fixed for the rebroadcast). They wrote back saying "the network sends it to us in 4:3."
Then, on rebroadcast, whaddayaknow? It was a in spectacular 16:9 HD!
I hadn't noticed it before (since only the Wipeout Bowl was HD), but there's quite a lot going on in the background there at the ranch. We can see construction of some kind during the qualifier (in addition to the ranch itself), and a lot more of the set around the Wipeout Zone (including what appear to be the gas pipes for lighting, fire, etc.)
We of course don't need to be told how much more of an immersive experience HD CAN be, but after suffering through SD last week, it made the rebroadcast all the more sweet.. er.. painful!