Like your experience with Helma, Grails has also been a breath of fresh air. My biggest gripe with building web apps in Java is dealing with all the dependencies, setting up a project structure and making all the frameworks play nicely together...with grails none of those headaches exist...all the stuff you'd usually use is integrated nicely into a project and with almost zero configuration. The community is very responsive and new plugins are released on a weekly basis. I definitely recommend any Java developers out there take a look.
