They COULD make it so the highest settings work on the latest cards, like the 8800. But instead, the
exact same settings are being called "High" and they're having extra settings (eg "Extra High") which are even higher. They could simply not give the option of settings that don't work smoothly yet, but instead they're going to give the option for the extra settings, then when the hardware's available the game will look even better.
It's not like "Oh I know what, lets make it run poorly on everyones computer", it's like "Lets make it so that, later on when people have even better cards, there's still some graphical improvements for them".
They're not taking
anything away, they're giving
more so that we have a game that's even more future proof, and will look even better in 2 years time when we don't think much of an 8800GTX anymore!
It will still look sexy on your computer and will be very fun. Just because your settings screen isn't on "Ultra High" doesn't mean it's not going to look good