I believe it was used for a few of the shots over the water in Herzogs: The Cave of Dreams"
but the photo of it alone is delightful.

It is the:
Skybot MK2 Aerial HD 3D Camera Rig from British Technical Films.

Photo and article:

Skybot MK2 Aerial HD 3D Camera Rig from British Technical Films - 3D Vision Blog (http://3dvision-blog.com/skybot-mk2-aerial-hd-3d-camera-rig-from-british-technical-films/)

I wonder if they managed to sync the two cameras.

Hello

It was the BTF skybot with 2 totally un-synced GoPro's, if You keep the cameras the same way (not one upside down) we could get away with the sync issues. But there are plenty!

I did the post for this film.
NB! But Chris Watts is a rockstar with his toy!
-Kaspar