Here's a rather interesting looking (still upcoming) full HD 3D action camera from the French company Camsports:
http://www.camsports.com/index.php?Itemid=283

I guess it's trying to compete with the GoPro 3D kit. I wonder if the camera sensors are better synced than the GoPro 3D ones. I was disappointed to find out that the sync cable doesn't actually genlock the GoPros, it just estabilishes a controller master/slave relationship. And the sensors are still off phase.

Good finds !

I also thought the GoPro cameras were genlocked, too bad the cable is only used as a master/slave command. The schematics could still be helpful to create a 6.5cm interaxial suitable for the Rift though.

Overall I'm pretty much disappointed by the quality of these cameras, I thought they were quite good quality but this review shows that they are worse than standard 2D cams. The sync and color problems in 3D don't seem to help either.

Unfortunately there is not a lot of choice in this market and it looks like the Camsports Fusion 3D has a quite small interaxial which will be impossible to modify.

The GoPro Hero3 has WiFi built in. There is a theoretical possibility they could genlock each other via WiFi, but GoPro haven't responded to people's inquiries on the subject.

Yeah, too bad the Fusion 3D IPD is too small. Maybe they wanted to make the camera more compact.

I was going to get a GoPro 3D kit for the sync cable but then I asked a friend to try if it synced exposure and white balance, which I guess is genlocking? As it did not, disappointingly, I will just run without a sync cable (and housing).

The Fusion 3D could have been nice, but as you say the IPD seem to be lacking, and the FoV is "only" 135° :P In this video they mention the possibility to have separate settings for each camera, which seems pointless if you want to use it for 3D. I know I never use my W3 for 2D... >_> for that I can use any of my other cameras.

Well this is a bummer. Looks like Camsports have removed the Fusion 3D from their page. The link now leads to a 404, and it's no longer mentioned there.

Guess the product didn't turn out the way they hoped, huh?