Learning OpenGL 4.0 with some familiarity with 1.2
I am trying to learn OpenGL 4.xx . I have some previous experience with OpenGL 2.0 and back in 2005 i used it to design a small game as a hobby. Around the same time i changed my field from s/w to research (went for a phd in pure maths) and have not since touched computer as a programmer. Now in 2013, i am again itching to develop some computer graphics purely as an interest.
Again i want to use OpenGL as the backend graphics API. But it seems a lot has changed since then (esp in version 3.0).
My questions are:
1) Will my previous knowledge and small collection of books on OpenGL (like 'redbook' and bluebooks for version 1.2 etc) be of any help or does one needs to learn everything from grounds up?
2) What are best books/online resources to learn version 4.0 ??