Official Nikon D300 Eye Candy
Here are some links to various Nikon D300 media files that can be downloaded right now.
Nikon D300 Product Gallery
There's a whole bunch of high-resolution and web-ready product images of the Nikon D300 that you can download at this site. Have a go at creating your own D300 wallpaper or screen saver.
Nikon D300 Brochure
A two-page PDF brochure is all that's available for now. And no, there are no sample images in there. Go to the Nikon Brochure Download section for brochures on other products.
Nikon D300 Special Site
This is specially dedicated to the Nikon D300. Expect more animations and tutorials in time to come.