DSLR News Shooter Dan Chung has posted some photos of his time at the races with the  Canon 1D Mark IV.
He also reports on a DSLR Video seminar he hosted in Singapore with Cathay Photo, Canon Singapore, and Genus Products.
Dan got to play around with two Mark IV Pre-pro cameras at the races. There is not a lot of info about the camera in the post.
He really only describes the LCD on the 1D Mark IV.
“I should mention that the LCD screen somehow seems to be better than that of the 5DmkII or 7D, it is the same resolution but I found it easier to focus with.”
There are some good photos in his report.