Well, I think it all depends on the set: some might work bettwe than others depending on how they were designed. For instance if you have a lower line model that was part of a family designed for 1080p at the top, it might actually do pretty good with 1080i input.

The flickering I saw on mine was completely unexpected. And it might just be placebo effect, but I swear that motion on 720p channels like Fox is actually smoother - more... "solid".