Indeed, I imagine 240Hz is off the hook. I wanted to get a 240Hz, but those were out of my price range for the moment.
If I recall correctly, I think I've even seen a couple of plasma TV's with a 500Hz range. If that's the case, I couldn't even imagine it.
However, I'm not a big fan of plasma TV's. (Video games and computers are not good for plasmas, even though current model Plasma TV's do apparently have some kind of burn-in rectification feature, I just wouldn't wanna chance it.)
I've got the entire series of the new Battlestar Galactica on Blu-Ray, and started watching the miniseries last night again. Holy FRAK! It looks like a completely different show in 120Hz.