What is the quickest way to come up to speed on OpenGL ES 1.x?

Let's assume I know nothing about OpenGL (which is not entirely true, but it's been a while since I last used OpenGL). I am most interested in learning this for iPhone-related development, but I'm interested in learning how it works on other platforms as well.

I've found the book OpenGL ES 2.0 Programming Guide, but I am concerned that it might not be the best approach because it focuses on 2.0 rather than 1.x. My understanding is that 2.0 is not backwards-compatible with 1.x, so I may miss out on some important concepts.

Note: For answers about learning general OpenGL, see http://stackoverflow.com/questions/62540/learning-opengl

Some resources I've found:

• http://khronos.org/opengles/1_X/
• http://www.imgtec.com/powervr/insider/sdk/KhronosOpenGLES1xMBX.asp
• OpenGL Distilled by Paul Martz (a good refresher on OpenGL basics)