.jpg, tiff, .obj, html, most fonts and Im sure many other technologies are able to be used seamlessly across most platforms. I believe the industry would be well served if industry standards were developed to discribe materials and shaders so that they could be used seamlessly across platforms. Im not a scientist but I would imagine shaders and lighting are based on well established concepts of physics.

Poser materials do work seamlessly across platforms, if by "platforms" you mean Windows or MacOS.

But I suspect you mean that materials should be portable between (for example) Poser and Cinema4D, or 3DS Max, or Blender. That's not going to happen any time soon, if ever, because for each render engine there's a different way of defining materials.

It's true that materials and shaders attempt to describe how light should behave in a more-or-less accurate fashion and in accordance with the same laws of physics, and that the underlying mathematics may well be identical, but the way this is implemented varies enormously between render engines.

I guess you could do a quick and dirty method by encoding the RGB values for Diffuse, Specular, etc, and the intensities thereof.  Likewise transparency, ambient glow and anything else you could  think of.  At its simplest, this could be in the form of a text file which could be read by the target app, which could implement a script or something to automate the conversion.

Poser may be more than halfway there because material definitions are stored as text but converting those values to - for example - Max is a whole nother thing.  

I think this falls under the heading of it it were easy, someone would have done it by now. So you have FBX, collada doing other aspects but not shaders. AFAIK, you may not even be able to take e.g. VRay shaders between Max and C4D. You get best effort approximations e.g. Poser to Lux. Even if the technical problems were solved, what may be in users interest not necessarily seen that way by companies.