You NEED to specify that target devices WILL support source code shaders.
If you don't, just don't bother doing a new version.
The current standard, isn't.
The spec basically says ...
you may or may not have source code shaders
you may or may not have binary shaders
you may or may not have oes extensions for shaders
How are you supposed to support all devices with this as a standard?
Either... sell out to a mobile phone company and become <insert company name here>gl instead of OpenGL, or do it right and make platform independence important.
This sort of thing is why Java is such a dog. Start out with a platform independant VM then start buggering about with it creating pJava and Midp, and all the rest of the sub species, make it impossible to write code that will work on all platforms and wonder why people stop supporting it.