What if Microsoft ever succeeds in its age long quest to eliminate OpenGL (at least
on Windows machine). Is JME able to be ported to Direct3D?
one reason y i hate MS and stupid directx
if that happens i'd say port jme to C# instead 8) (or just start over s)
it's not the first time you suggest this 
Well since DirectX and OpenGL are both interfaces to a video card this shouldn't be too difficult (and for the same reason not really necessary), the only problem I see is having to use HLSL instead of GLSL/ARB for shaders.
What if Microsoft ever succeeds in its age long quest to eliminate OpenGL (at least
on Windows machine). Is JME able to be ported to Direct3D?
1. For pc-desktop there are people on mac and linux (and many other operating systems) that only use OpenGL. While MS-soft might reduce the market share of the other operating systems (and so far MS-soft is slowly loosing the market share), it will never be able to eliminate them.
2. Most of embedded electornic devices and cellphones use JavaME. And Java is there to stay. Many of those devices will implement Java binding for OpenGL ES. Again, OpenGL is there to stay.
3. If openGL is alive on other system, it means it's still alive and MS-Soft is not capable of simply "banning it on windows".
4. If what you are describing will happen and MS-Soft has won, then porting jME to DirectX will be your last concern, because MS-Soft will make sure to kill and demolish any open source initiatives. In fact, if you let MS-Soft have their way, you would need to purchase a license to use their api, just so can program at all.
There has been some effort on the LWJGL side of things to support DirectX. If they succeed in doing such a binding, it would make things much easier, we would probably just need to implement LWJGL* classes as LWJGLDX* classes (depending on how they implement the binding).