There are no limitations on what I can write. The only limitation now is my available time, which is quite restricted this week, and before the week is over I'll be leaving for a two week long shoot in Madagascar.
I've had the 1Ds MKIII now for a week and have done some limited shooting with it. I will be taking it to Africa as my main camera and expect that I'll be able to really put it through it's paces there.
For the moment what I can say is that the camera is simply terrific. Image quality and sensor aside, it's just like a 1D MKIII. The bodies are essentially identical, with the IIIS having a slightly larger prism bulge.
So, if you want to know what the IIIS is like as a camera, simply read my and other reviewer's comments on that camera.
As for image quality, it's simpy too early to tell much. I've done about 400 frames so far, shooting fall colour in Algonquin Park. I've made about a half dozen 20X30" prints today on the new Epson 11880 printer, and the results are excellent.
Auto white balance is as good as I've ever seen. Tonal renditions are excellent, and while I've done no noise comparisons yet, ISO 400 frames are essentially noiseless and ISO 800 hardly need any additional work. I have not yet shot 1600 or higher.
The extra pixels are very welcome for either making big prints, or cropping. I have not done any comparisons yet to a 1D MKII or the 5D (I plan on doing this before my review appears). I briefly did a comparison with a P45+, but that's comparing apples and oranges. The 39MP camera without an antiailiasing filter is head and shoulders better in terms of resolution than a 21MP with an AA filter.
But having said that, my quick summery is that the 1Ds MKIII is Canon's best camera yet. Superb image quality, much improved features and user interface, better battery system, faster frame rate, etc etc.
There's still a great deal for me to analyse, but it will be several weeks until I am back from my shoot in Madagascar and have a chance to write a full hands-on review.
And, to answer the question that will inevitably be asked, no, I have not tested focus tracking, and don't know anything about how, if, and when Canon will handle the reported focus issues with the 1D MKIII and by implication the 1Ds MKII.