First off, I really enjoyed your (Cay's) book "Big Java" which I read over the summer in preparation for my ap-cs class since I was skipping intro. It helped a lot and I'm now one of the top students in the class.
I was wondering, what are the big differences / what will I learn from core java over big java?
I have Core Java 2 Vol. II - Advanced Features In my opinion, the best advantage of this book andthat it explains very clear the core JAVA API and the code examples are very objective unlike books that i�ve seen that use to many unnecessary code like the book "How to program" that dirty the code with a lot of unnecessary Swing/Awt code.
Big Java is a college text for a CS1 course. It is an introduction to programming and object-oriented design, written for college students (or bright high school students) without prior programming experience. It is a book for CS majors, so there is a lot of emphasis on software engineering principles.
Core Java is a professional book, written for professional programmers who want to learn about the Java language and library. It goes into a great amount of detail into those parts of the standard library that are likely to be used by application programmers.
I don't think that readers in an "intermediate Java" forum would benefit from Big Java--presumably you all know how to program. But if you worked through Big Java or a similar book in your college or AP course, Core Java would be a natural follow-on.