Together with a new netbeans.org page design, version 5.5 was released. It IS a great improvement over 5.0 since it supports Java EE5.
But myself will be more eager to use version 6.0 as it will contain many new improvements for the editor itself. Can't wait! :)) I've tried them with a build from the trunk and the editor is much better compared to now. Code completion is more context aware and a lot faster. I still have to test it with a large projects that I'm working on, but the infrastructure itself promises a lot. :))