Here is how I see the new line up shaping up.
7D - $1299
5Dm2 21mp FF - $1799
5DX - 22mp FF 61pt AF, 6.9fps - $2499
3DX - 40mp FF 61pt AF, 4fps - $3499
1DX - 18mp FF 61pt AF - 12fps - $5999
I hope canon also makes a budget FF camera. Imagine if the 7Dm2 was a 12mp FF for $1000 that would kill nikon
Although I'm not sure why everyone keeps calling the 3D the slow, fat MP body when the EOS 3 and the fabled 3D everyone has been going on about was always said to be a pro AF, high speed, compact FF.
So I'd swap your 5D3 and 3D names and I would raise the re-labelled 3D price to $2700+ and lower the 5D3 price to $3200.
In 2015 or so the 3D2 bumps up to 39MP and retains 6.9fps and top AF and then we really have a nice all around camera and the 5D4 get cancelled or becomes a much slower, less expensive 39MP body than the 3D2?
For now, some will prefer the D800 and some the 3D.
If the they have fixed up the DR on the 3D/5D3 and haven't crippled the 1DX AF in it more than a trace (and I don't think they should since the D800 will do 6fps in DX mode with grip and 36MP, two pretty decent things! plus have Nikon's very best AF attempt! and uncompressed 1080p out) it will be pretty cool, awesome video, great speed and performance, top AF, compact size. The only thing it will lack is reach, it will be somewhat weak for wildlife, and the detail for hyper ppi 13x19 or for 300 ppi very large size prints, everything else would be everything you want (other than pro sealing, pro durability, hyper fps for the most serious of action shooters, for the ones who must have that they will pay for the 1DX).