It's great to see the Netbeans QA process working so well. I reported two issues recently, and both have been fixed. One was a Subversion related issue; within 24 hours I was contacted by the developer assigned to the issue, and offered a patched jar to try! It fixed the problem, and the patch will be rolled-up in v6.5. Impressive.
Netbeans is getting better, faster, than anything else out there, as far as I can see. There are some things I still don't think are good enough yet (such as the UML support) and I wish the whole thing would start up much more quickly, but it's important to recognize just how good this tool already is. And it's a free, small download. The comparison with Visual Studio is almost irresistable; VS is a DVD's worth of code, costs a fortune and offers a much less capable code editor, less refactoring support and doesn't really support rich client development to the extent NB6 does.
Look the the Ruby support in NB6, too: although there is a lot of interesting work going on with dynamic languages at Microsoft, the impression you get is that these are somewhat 'second-class' projects with no real presence in the main-line Visual Studio product plans. JRuby, on the other hand, is almost front-and-centre in the Netbeans world. The integration of languages via the JVM, and the development of integrated tooling in Netbeans makes it possible to do serious work with Java and Ruby, right now.
Another thing: Sun isn't trying to shut-down or marginalise any of the community, open-source projects which populate the Java tools landscape. Instead, they've recognized and accepted the strongest members of the community and built tool support for them in Netbeans. Just take the most obvious examples: Ant, JUnit and Maven. Compare that with what Microsoft has done: ignored NDoc and produced Sandcastle, created MSBuild to replace NAnt, and they want you to use (therefore buy) their own version-control system rather than embrace Subversion or Mercurial. I'm sure Team System is probably fine, as long as you have deep pockets and you are prepared to submit totally to Microsoft's prescription for your development team processes.