I have both (well, the Red Book is from the library, but still).
I found that the Red Book is good for telling you the different commands, but in the way of source code examples, it is decent, but could be better.
Neither book tells you what you need to do to setup VC++ to use OpenGL. Well, the OpenGL Game Programming book does, but not until the last chapter or so, which doesn''t help me if I am frustrated from the first few chapters not working, right?
Anyway, I found I learned a lot more from the OGP book since it is specific to the WIN32 platform. In fact, my first Windows programs were made because of this book. Otherwise I would have been a little too lazy to push myself to make my own programs.

I would suggest getting both if you can, but if you want to learn very specific WIN32 coding, go for the OGP book. If you want to learn about the OpenGL API in a more independent setting, then I would suggest the Red Book, but only as a reference really. It has source and explanations, but I didn''t feel I really learned too much or very easily from it.
That''s my opinion.