In my ongoing evaluation of various web frontend frameworks, I stumbled upon the ZK Open Source Ajax (among others like IceFaces, JMaki/Dojo/Comet, JSF Controls). Even ZK appears a bit more on the Eclipse side it can easily be used in Netbans. In order to get the ZK implanted in our favorite IDE, you need to download the plugin from Sourceforge (link). Please note the startsite on ZK (SF) highlights the current version 2.0.3 from March 2009, but clicking on the download link on the right points you to the old version, so you better select the browse packages link.
Link to ZK Website
Link to SF REM 2.0.3 Plugin
Start Netbeans and open the Tools/Plugins/Downloaded and add the downloaded plugin (with the usual agree and confirm unsigned plugin dialog.

REM 2.0.3 NB plugin
That’s it ! Welcome to ZK in Netbeans.
Start a new web project and select the ZK 360 option.

ZK360 Project
You will find a project skeleton with an initial index.zul file

ZK Project Skeleton
Start the application and it gets deployed to Glassfish (or you choice of AS). So far I have no problems running it on Glassfish V2 and V3 prelude.
I run through the evaluator tutorial with ease (link).
Stay tuned for more hands-on with Netbeans and ZK.