This is just a theory. And let me first off say that I am a landscape photographer. I shoot some news and weddings, but primarily landscape. And I'll say that I was disappointed that the 5Diii wasn't higher MP.
I wonder if the reason that almost all the new and updated features in the new 5D are geared for wedding, sports, nature, news shooters because these are the types of shooters that DSLRs are geared toward naturally. Would it be true that most studio and landscape shooters that make the serious dough use medium format digital and full frame film. Where those who are on more limited budgets settle for DSLRs as a budget option. Afterall many features that are on DSLRs, even the idea of a single-lens reflex system aren't necessary for a landscape photographer, and some such as an SLR system even limit quality. Aren't optics more difficult when needing to put a mirror in the way of the lens and sensor vs. a rangefinder system.
I'm not saying that professional landscapers and studio shooters don't use DSLRs and some make a good chunk of change. But in general DSLRs are designed for the exact audience that the new 5D seems to be geared for.
So I think that canon looks at the bottom line and realizes that no matter how many people want more megapixels there is simply a bigger market that wants low ISO, FPS, etc.
My hope is that Canon comes out with a camera that does fit that niche market. I'd pre-order it in a second.
Like I said, I'm just proposing a theory. Anyone have thoughts?
Most MF camera are DSLR's aswell of course but I do think its a good point, the 1DX is arguebley the best high end FPS/AF/ISO tool money can buy with the 5D mk3 not far behind so they tap into a higher end market. High megapixel FF DSLR's on the other hand are operating in the middle ground between normal FF/Crop ones and MF.
Ther 1Ds mk3 wasnt a great seller not just due to competision from the 5D mk2 but also from MF like the 645D coming down in price. Nikon's D3X wasnt a great seller either and that lacked any competision from a cheaper Nikon SLR with the same sensor afterall.
The recent interviews with Canon on this subject did seem to give the impression that it was going to be a "wait and see" with reguards the D800's performance.
I'm actually supprized that there hasnt been some form of mirrorless MF camera(well besides scanning backs) since to me that seems like a great fit just as it was for MF rangefinders and film. The savings in size/weight/cost obviously get greater the larger the sensor and if your dealing with landscape and studio users alot of the lenses are going to be in the wide/normal range where mirrorless could save space there too. The weakness in AF is less of a problem for such users and with an EVF not being able to see the effects of filters isnt a problem anymore either