...and an 8×10 Sinar will produce higher quality than a Nikon F6. So what? Try shooting sports with an 8×10!
If sheer quality is the only criteria, then perhaps, but the X-pro1 and D800 are as fundamentally different as two pro-level digital cameras can be. One factor out of a whole range of factors, and any camera comparison must compare cameras as a whole. In the case of these two cameras, it is almost impossible, since they operate within very different contexts.
At this time in the evolution of digital camera technology, I have no feeling whatever that the D800 is "pushing it". The D7000 with similar pixel density does just fine, and is two years older technology. In 2012, 24-36MP should be seen as normal. When I bought my D700, there was almost a mathematical relationship between pixel density, noise and high-ISO performance. That was five years ago when the D3/D700 sensor was current. Times have changed, the relationship no longer holds. A 36MP full frame sensor is just not that special.
While the D800 mitochondrial DNA is clearly that of film SLRs, the DNA of the X-Pro1 is that of rangefinders. Had Kyocera not killed the Contax brand, and had Contax been able to evolve a digital version of their G2 camera, it would almost certainly be very much like the XP1. The experiences of shooting a D800 and an XP1 will be very different—so different that one can not compare. My XP1 is on order, but my D700 has no fear of parting from me. Each serves a very different need and there is virtually no cross-over.
That said, I have very high expectations for the XP1. I feel that most sample pictures tell a lot more about the photographer than they do about the camera, but clearly the camera delivers. The D800E has no effective AA filter, and leaves it up to the photographer whether one is needed. Clearly in a perfect storm of circumstances, moire will impact an image from time to time. Fuji has abandoned the venerable Bayer mosaic for the colour filter array based upon a 6×6 rather than a 2×2 cell, with a pseudo-random arrangement that is meant to simulate film. No AA filter needed under any circumstances—if this truly works. With no need for an AA filter, the full potential of lens and sensor should be achieved.
As an aside, I was reading about the X100 in DPReview. It either has no AA filter, or the very lightest of AA filters, and they reported that it comes very close to achieving the full potential of its 12MP sensor. Even with an arsenal of excellent Nikon glass, I feel it is my sharpest prime. Not only that, but it comes with a lovely little camera hanging off its back.
So based upon pre-production and early production samples, for the single criterion of image quality the XP1 may well be the finest 16MP, APS-C camera, and sort of in the same league as the D800 with-full frame 36MP, with and without an AA filter. I certainly would not presume to judge. However, I do have the XP1 and three lenses on order, but not the D800—so obviously, I voted with my wallet. My "ancient" D700 is doing just fine for dSLR duties and may continue to do so for the rest of my life.
