In regards to throwing the Canon and Leica M9 into the mix, I enjoyed reading it. While other readers may not be too happy with it, or consider it fair, I appreciate the comparisons just the same--one cannot own all of the tools to compare and my main concern with MF digital at this point-in-time, is sharpness and DOF (cost as well).
If I travel to shoot specifically for landscapes and find that I get superior results when shooting my Nikon and stitching, I cannot help but question why should I invest in MF digital for this purpose? I have yet to receive the "WOW" from my MF digital landscape kit, but before I sell it off, I will be asking my vendor to take it all back and to please tweak all of its components for the "wow." I feel there is something missing in my expensive landscape kit and the experts should have a chance to test it, tweak it, and charge me for the necessary time to bring it all together (if possible).
I do have one request in regards to your mentioning of testing 67 lenses with the 645D: I would be interested in seeing how the 100 F4 SMC Macro performs. I have a beautiful-performer of this lens, plus the 55mm, zoom 55-100mm, and 165mm LS in my kit. I will ship any or all of these lenses to you free of expense and liability for testing if you are interested. (Please PM me if you are interested.)
The biggest reason I have held onto my 67II kit is because of its superb performance in regards to sharpness and DOF. If I eventually buy into the Pentax 645D line, I will want to use my 67 lenses.
I understand this is the first generation of the 645D and I do not expect it to be stellar, but I am willing to contribute into their Research & Development (R&D) fund more-so, than anyone else at this time. I have made my living as a photographer for over 30 years, and I do not plan on stopping anytime soon, but I have grown disappointed with some of the industry and have lost a bit of trust in their concern for professional needs and simplicity of design.
Pentax has made me hopeful, and it is easier for me to trust their future with my dollars mainly because of the "WOW" factor I repeatably receive through their equipment and their timing into the MF digital market. Pentax IMHO, seems to have waited on the sidelines, observing others R&D before they went to their own drawing board, and this I like! It is a smart business model and one that I think will eventually pay-off.