Sun engineer Matthias Schmidt has just published an article on the progress of the Groovy and Grails support in NetBeans [1]. The Aquarium [2] also features the ongoing work on support of Grails in Glassfish [3].
On NetBeans front, Matthias Schmidt and Martin Adamek started working on a plugin back in November. You'll need to use a NetBeans nightly build [4], and download the Groovy/Grails plugin from the updace center. The plugin already provides:
On GlassFish's side, Eduardo Pelegri reports [5] improvements and bug fixes for running Grails applications in GlassFish [6] and shares a link to the roadmap of the Groovy/Grails support in GlassFish [7].
Links:
[1] http://blogs.sun.com/schmidtm/entry/news_from_grailsland
[2] http://blogs.sun.com/theaquarium/
[3] http://blogs.sun.com/theaquarium/entry/netbeans_support_for_groovy
[4] http://deadlock.netbeans.org/hudson/job/trunk/lastSuccessfulBuild/artifact/nbbuild/dist/zip/
[5] http://blogs.sun.com/theaquarium/entry/netbeans_support_for_groovy
[6] http://blogs.sun.com/theaquarium/entry/kicking_the_tires_of_grails
[7] http://wiki.glassfish.java.net/Wiki.jsp?page=GroovyGrailsPlanning