Java 9 will include many new features beyond just Jigsaw modules, including enhanced method handles, modular application packaging, and dynamic linking capabilities. It may cause some code to break, so developers are encouraged to try it out now rather than later. Java 9 will improve performance in areas like locking, graphics, and hardware usage. Tooling is being updated for Java 9 as well, with IntelliJ IDEA gaining features like automatic module-info generation and JLink artifact support.