Chaos Group released this information regarding Vray 3 for Max and Maya 2016 users.
Currently V-Ray 2.0 for 3ds Max 2015 will work with 3ds Max 2016.
The same is not true for V-Ray 2.0 for Maya 2016; there is no V-Ray 2.0 build that will work with Maya 2016.
V-Ray 3.0 for 3ds Max 2016 users should contact email@example.com and request access to the nightly builds, where V-Ray 3.0 for 3ds Max 2016 is available to download. They are also preparing a nightly build of V-Ray 3.0 for Maya 2016, which users can access by contacting them directly.