<p>I'm a very experienced Java programmer who has spent my entire time working with Java 1.4 and earlier.  Where can I find a quick reference that will give me everything I need to know about the new features in Java5 and later in a quick reference?</p>

Here's a good place to start:
https://docs.oracle.com/javase/1.5.0/docs/relnotes/features.html
http://java.sun.com/developer/technicalArticles/releases/j2se15/