This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
On http://java.sun.com/javase/reference/api.jsp you can find links to the full documentation of all major JRE releases. The release notes of each one have a section titled "What's new" or some such; that should provide what you're looking for.