The GWT4NB project aims to enable developers to take advantage of both: the superior support for creating Web Applications built into the NetBeans IDE and the power of GWT (Google Web Toolkit).
Click here for the full list of the features with screenshots.
See also Ohloh
JDK6 and 7, GWT 1.5, 1.6, 1.7, 2.0, 2.1, 2.2, 2.3 and 2.4, NetBeans 7.0, 7.1, 7.2, 7.3 and 7.4
The NetBeans IDE is a free, open-source Integrated Development Environment for software developers. The IDE runs on many platforms including Windows, Linux, Solaris, and the MacOS. It is easy to install and use straight out of the box. The NetBeans IDE provides developers with all the tools they need to create professional cross-platform desktop, enterprise, web and mobile applications.