The A7rII will soon get a firmware update with 14BIT uncompressed RAW and maybe some other additional feature. So most reviewers here below will have to rewrite some piece of their review :)
Anyway, here are the latest A7rII tests:

A7R II and 90mm macro underwater piece (Imaging Resource).
Sony A7RII First Look By Mason Marsh (StuckinCustoms).
Sony a7RII Canon EF Smart Adapter Tests (Brian Smith).
Canon EOS 5DS R Versus Sony Alpha A7R II Comparison (ePhotozine).
α7RII and legacy wide angle lenses (The.me).
Sony A7R II: Other Areas That Need Attention via Firmware Update (Diglloyd).
Sony Alpha A7R II review (Techradar).
Sony a7S II vs a7R II vs a7 II (Digitalrev).
Using the New Sony a7R II at 150 Miles Per Hour (Alphauniverse).
Sony A7R II: la función de vídeo a examen (Quesabesde).

A7rII store links:
In USA: at Amazon, BHphoto, Adorama, SonyStore US, FocusCamera, Uniquephoto.
In Europe at Sony DE, UK, FR, IT, ES, NL, BE, CH, AT, SE, FI, NO, PT. Wex UK.
In Asia at Digitalrev, CameraPro.

The Sony A7sII now got listed at Amazon US too (Click here). Preorders will be available tomorrow (Sept 17) at exactly 12am New York time at all US stores. Direct link here: Amazon US, BHphoto, FocusCamera and Adorama.

Two video interviews:
First Look Interview with Sony Manager Kenta Honjo (SonyAlphaCameras).
Sony’s new a7S II fixes the biggest problems with the original a7S. Is it worth the extra cost, or should you buy an a7R II instead? (Tony Northup on SonyAlphaCameras)
Interview at IBC from Victor Bart.

Amateurphotographer writes:

The A7S II looks like a fantastic camera that buckles the trend for cameras with increasingly high resolutions, and that is what many photographers have been asking for. They don’t want more and more pixels, they want a higher dynamic range and less noise.
The real test will come when we have a full working sample of the camera and can see exactly what the differences in image quality are between the two cameras. For videographers there is certainly a reason for the new camera, whilst professional wedding and event photographers will surely make a beeline towards the A7S II and its quieter shutter, faster focusing and image stabilisation.

Digitalcameraworld writes:

The ability to record 4K in-camera allows these users a bit more freedom plus the ability to travel lighter and work more discretely. Meanwhile the improvement in the AF and noise control will be widely appreciated.
Those looking for an ‘all-rounder’ camera are best off looking at the A7 II, or even the A7R II if they can stomach the cost, but the A7S and A7S II are intended to produce the best image quality.
The A7S really impressed when we tested it and the improvements brought by the A7S II should make it even more attractive.

More A7sII hands-on:
First Impressions: Sony A7s Mk II (ThePhoBlographer).
Sony’s A7S II is a 4K-shooting pro for your darkest moments (Engadget)

Preorders:
Soon at Amazon US, BHphoto, FocusCamera and Adorama.
In Europe at ParkCameras UK, Verkkokauppa in Finland. CVP in UK.
in Asia at Digitalrev.