Top 10 New Java Features in NetBeans IDE 6.5

the highlights of these are, in my opinion, the following, in order of significance:

1. Performance Improvements. If there is one area that every Java programmer (indeed, any programmer at all) is interested in, it is performance of their IDE. Discussions on this theme rage all over the web—the IDE that, despite its growing feature set, continues to be (and enhances the extent to which it is) performant is the one where most programmers will flock to. More so than any other (assuming the feature set is competitive), this is the distinguishing feature between IDEs, if the difference between them on this point is significant enough. Even more so than before, NetBeans IDE
2. Compile & Deploy on Save. One of the key features that has distinguished NetBeans by its absence, 6.5 now includes. Better than describing it in words is to show it in action. Watch the video below for details.
3. Groovy. More than any other scripting language, Groovy lends itself to handling the heavy lifting of traditional cumbersome Java tasks, without requiring you to make a huge mental shift to start using it. The ease with which this is possible is quite amazing: 
4. Java Editor Enhancements. An area where NetBeans IDE has consistently improved, while continuing to lag over its peers, is the Java editor, in terms of its performance (see above) and, in particular, its range of refactorings. In fact, any presentation done by any NetBeans presenter (ever, I dare say) has been followed by the question/statement
5. Code Completion. The jewel of any code editor is, I believe, together with the "hints/tips" feature (so wonderfully represented in IntelliJ), the code completion feature. Any enhancement in this area, after performance, is inevitably very fine grained, which is exactly the level at which code completion is most useful. One enhancement in this area to have made its way into IDE 6.5, is CamelCase code completion: