Buy. Or wait...the update to the 1D X should be along in 2-3 years.
Why do say that? Seriously I would like to understand your logic. FOr example the 1Dx is about a year old and based upon history the 1Ds was updated every 3-4 years. Is that correct?
The 1DX is 18 months old, no other 1D has gone more than 36 months apart from the 1Ds MkIII, and the 1DX is NOT a 1Ds MkIII replacement. This gives the 1DX a historical replacement cycle of within the next 18 months.
Maybe. Canon could have totally lied when they stated that the 1Ds and 1D lines were being merged in the 1D X. But they stated that - explicitly.
There was a very good reason Canon and Nikon made two very distinct "pro" bodies, one very much orientated to sports and general shooters, the other orientated towards studio and landscape. Now the D800 has proven that much higher mp can be used effectively by the best glass, you don't replace a 21mp camera with an 18mp camera when your competitor just went from 24mp to 36mp. Even if the high mp Canon is not a 1 series, it doesn't alter the point that the 1DX is looked on as a "sports/general purpose" camera and these tools have typically had a less than three year lifespan.
Exactly. The hypothetical Canon high MP body might be an EOS 3D (or whataver), a non-1-series body. Also, you seem to be starting your clock from the announcement of the 1D X, not it's actual release. The length of time from announcement to release for the high end stuff seems to be growing, not shrinking. So even if the replacement is announced 32 months after the last announcement, the real availability might be 3.5 years or more.
I guess we'll just have to wait and see. I do think that Canon is putting less emphasis on the 1-series - they're making a great camera, but the consolidation of the two sub-lines is an acknowledgment that while the flagship is important, it's not a major contributor to their dSLR revenue.
We will have to wait and see, of course, but if the high MP camera is a 1DXs, then the current "sport" shooters dream, the 1Dx, would be in line for replacement in about 12-18 months. If the 1DXs is a "3D"/D800 then the 1DX is due for replacement in 12-18 months!
Many things will factor into the equation, most of which we will never know, but if Canon are developing a big MP sensor, and they must be, the majority of the actual body R&D costs are recovered by the 1Dx so the 1DXs shouldn't cost Canon too much money and effort, they wouldn't need to spend huge money developing it or recover huge money in sales. They almost certainly made the 5D MkII to recover R&D costs and lower manufacturing costs of the 1Ds MkIII sensor. If/when Nikon come out with a 1D4x then their hand will be played, they will have to answer, at the moment the 5D MkIII stacks up very well against the D800, but there is a good high end market for these $7-8,000 cameras. Even if Nikon don't come out with a D4x they will come out with a D5, in about 12-18 months.
Heck put a 5D MkIII sensor in a 1Dx, lower the frame rate to 10fps, do the usual 1 series software tweaks and you already have the 1Dx MkII, I'd buy two of them.