VR Zone has published another review of the new GeForce GTX 280 to see how this card performs against the GeForce 9800 GX2 in high resolutions. People don't buy a $649 card to play at 1280 x 1024 so the site mainly focused on 1680 x 1050, 1920 x 1200 and 2560 x 1600.
At 1680 x 1050 and 1920 x 1200 the GeForce GTX 280 is not much faster than a GeForce 9800 GX2 but when you crank up the resolution to 2560 x 1600 on a 30" LCD display you really see the raw performance this beast has to offer.
Here's a quick overview of how much better the GeForce GTX 280 is in 2560 x 1600 in various games:
Enemy Territory: Quake Wars (High Quality): 28.8%
Crysis (High Quality): 709%
Crysis (Very High Quality): 820% (but still unplayable!)