This integration can be found in NetBeans IDE 6.0 Milestone 10 (M10). However, by reading Tor Norbye's blog I learned about nice features that are only available with the daily builds. So I decided to download a recent build and give it a try.
Here's some things that I found interesting and useful:
Debugger
Nice debugger integration with the IDE.
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Highlight block open/close element
This is a very useful feature to find out if nested blocks are closed.
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Code navigator
To quickly program elements inside a file.
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Hints
Display hints to improve the code or fix a bug. For example while editing a program from a previous post it showed me this:
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Also it suggest a fix for that issue:
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Very nice!