It's just as odd as using OpenGL from Java, right? The main issue I've seen people have with Go and using it for gaming or heavy graphics use is that it is garbage collected. But compared to the Java Hotspot runtime, it's gc isn't nearly as robust.
For whatever it is worth, Notch has said that when Oculus initially approached him for Minecraft on the Oculus, he identified performance being an issue as the Oculus would require a steady 90fps, which Minecraft would struggle to provide on some hardware. He identified using Java as one of the reasons that this was the case.
Before the Mojang/Oculus connection was severed in the Facebook/Oculus fallout, the plan was apparently to make a stripped down version of Minecraft, similar to Pocket or Pi, for the Oculus.
I think calling OpenGL from Java for performance-critical applications is an odd choice as well. I think the relative performance of native versus ART android apps is a good example of that.
Not that it's impossible to keep framerates up using GCed languages. But framerate will be extremely important for applications that more or less require screens with higher refresh rates than commodity LCDs.
