Upload & Sell: Off
A 5D2 with 7D AF swapped in and 18MP and 2/3 stop better and everything else the same would be incredibly lame after four years IMO and I think it might flop (one can get the speed and no line skipped video in a 7D2 or jsut the video in a 70D and with the way Canon pricing has been going maybe it costs $3000 and you can sell a 5D2 for $1600 so you need to spend $1400 to get that and you will then have that for the next four years. lame.
As far I remembered thousends of people called the 5D MK II improvements "lame" three years ago.
It developed to one of (if not) the most successfull body in itīs range and even kicked away all competitors and 1Ds MK III from itīs throne.
I honestly bet the D800 specs would crush that.).
Fine. I am with you. It would give me the chance to get the advantadges of Nikon gear, too. And it would force Canon to feed us with some more. Thatīs great, isnīt it?
If it had your 3 stops better that would be something although still quite a shame to be stuck at 3.9fps for only 18MP, but believe me the 1DX just is not going to be 3 stops better SNR middle gray than the 5D2. Heck even Canon marketing is only saying 2!! And even they have already admitted that some deal of that is simply due to internal jpg engine NR improvements!
That is new to me as far as I remember 51K should have comparabel quality than 6.400 has had in 1D MK. I shoot in raw and there is no in camera NR that could not be done (better) in raw development. But anyway: Two stopps are realy great, right? That would mean 12.800 without rework, 25.000 with some for the 5D MK II follow up. That IS great.
if we are very lucky it could conceivably have 3 stops better usable DR range but there are some early worrisome signs that canon won't match the sony sensor deep shadow cleanliness
as for d700, if all you do is tripod work yeah i'd take the 5D2 any day over a D700 (and even moreso if you do video work )
I owned a monopod, used it one time and sold it. I had a tripod, too. Used it three times and sold it.
And again: The D700 is great! I would have and use one if it would give me "some" more than 6 year old standard of competitors in resolution. And if any announced D800 will offer me, I will be glad and check it, too.