Yep, I'm sure there are still great nuggets in the book. Unfortunately it looks like I'm not going to get my question answered about modern OpenGL books because everyone just jumps in and says that you should still read Abrash's book.
John Carmack, for example, didn't write much of his games in assembler because he knew that he didn't have to. If you look at Doom, there wasn't a lot of assembler even back in the early 1990's.
https://github.com/id-Software/DOOM
And according to Carmack, he liked working in C and OpenGL.
http://rmitz.org/carmack.on.opengl.html
"With OpenGL, you can get something working with simple, straightforward code, then if it is warranted, you can convert to display lists or vertex arrays for max performance (although the difference usually isn't that large). This is the right way of doing things -- like converting your crucial functions to assembly language after doing all your development in C."
I actually have done some basic assembler so I do understatnd the benefits of keeping values in registers, etc. A lot of stuff really is architecture dependent, of course. ARM vs x86 will make a difference.
Anyway, where's the best place to start these days? Personally, I'd like to do some iOS stuff, and perhaps keep the same code running on Android.