has a preview up of the Lost Planet demo with a few benchmarks comparing a Radeon HD 2900XT to a GeForce 8800GTX. It seems like ATI are having some major drivers issues here as the demo isn't rendered correctly.
It looks like ATI doesn't support motion blur at all and this is even with a "feature preview" driver. According to Legit Reviews, some parts of the demo aren't rendering right and others are just missing.
If this wasn't bad enough, the Radeon HD 2900XT has abysmal performance compared to the 8800GTX. The Nvidia card is two to three times faster depending on which area of the game you're playing.
You can check out the full story over at Legit Reviews here
and you can compare the screen shots in terms of quality between the two cards.