Inversely, would you pit that same Nikon against the P65+ in the studio, with strobe, at full rez, at ASA 50? No, you would not.
No I wouldn't, but I do think before I spent $40,000 for this 60,000,000 pixel P65+with sensor Plus, I'd take a hard look at the 56,000,000 pixel Leaf 10 that cost $25,000 plus a 25,000,000 pixel Nikon D3x that sells for $8,000 and still have another $8,000 saved in my pocket.
There is a lot of zeros in that statement, but I guess we've become accustom to a lot of zeros in financial numbers lately.
Actually, I would like to have higher iso from medium format, but I doubt seriously if I would pay an extra anything for 15mpx higher iso, regardless of how these crops are received.
Edit: In the process of writing the above, I was stopped to go into a conference call on an upcoming project. We talk soul, depth, story, lighting, locations and of course numbers, but nowhere in this conversation did anybody mention megapixels, 800 iso noise in shadows or can the image be cropped down to 12% of the original frame.
Photography is not about science, it's art aided by science, not controlled and I do applaud that this phase back is trying to give us more options in regards to higher iso, but there is so much that gets missed that we really do need and really do keep asking for that I wonder if anybody that makes these cameras listens past the first few sentences.