Regarding Graphics Library Development

Greetings,
I am working in program development in Visual C++ using OpenGL library.

I have got an opportunity to develop the APIs of OpenGL ES and APIs of other graphics libraries in C++ for mobile handsets. I dont know how much interesting work is this Graphics Library development.

(A) Is “graphics library development” work more interesting than “using the graphics library in program to generate the scenes”.

(B) Is OpenGL better than openGL ES?

©What is the future of OpenGL ES, what are the areas where is it used.

(D) What are the companies which works in OpenGL ES and where I can use the experience of Graphics library development work.

I will really appreciate the replies from senior members to give advise.

Thanks alot for reading and thanks in advance for replying.

Regards,
Andy

A. I find both interesting
B. it is different, GL is for workstations / games on desktop PC/MAC, and GL ES is for C below.
C. already the widest used 3D API on phones and mobile devies (Apple iPhone etc)
D. http://www.khronos.org/opengles/

Thanks for your valuable reply

A. (1) is OpenGL ES a subset of OpenGL?

A. (2) Will I be able to come back to OpenGL after having worked in OpenGL ES or I will land up making my future restricted and limited to the OpenGL ES only.

C. Do you wanna say all the iphone makers works in OpenGL ES.

Thanks alot for reading and again thanks in advance for reply.

Warm Regards,