I just noticed this. Matt if the 800 px wide is dead then why is this forum 800 wide?
I agree that there are many more large screens that handle the wider resolution. With that said I still think that many people don't view at that resolution because the text is too small. On more than one occasion I'll walk into a clients office and they have this wonderful 22 or 24 inch wide screen set to 800 x 600. And the site that I designed for them is super-sized.