As you're probably already aware if you follow such things, Canon has announced the latest upgrade to its high-speed "photojournalist" flagship camera, the EOS 1D, moving from Mk. III status to Mk. IV.
For a brief executive summary of the changes, try Lori Grunin's article on the Crave Gadget blog at cnet news. A very brief pull: "The reputation of the EOS' AF system has taken a beating over the past couple of years, and Canon seems to have pulled out the stops to redeem itself...."
For a more in-depth but still digestibly pithy overview, look to Rob Galbraith's article.
The nutshell-nutshell version: 16 MP vs. the Mark III's 10; 1080p HD video similar to that of the new 7D; Nikon D3s-matching 2-stop boost in the highest ISO; and $5,000 vs. the Mark III's $4,000 (although remaining stocks of the Mark III are mildly discounted now). Somewhat surprisingly to me, the new Canon retains the oddball APS-H 1.3X-factor sensor size. Are Canon-shooting p-js just used to it?
The new camera is expected to ship in December. It's available for pre-order on Amazon, although Amazon warns that demand will be high and supplies from the manufacturer will be limited.