The Gradle team (thanks Szczepan and others) fixed a crucial bug impacting, at least, NetBeans IDE and so now the Gradle/NetBeans plugin is coming along OK. Click to enlarge the screenshot and notice the dependencies and Gradle targets shown in the left side of the screenshot and the Groovy editor on the right hand side:
Still lots of work to do, especially would like to have a Gradle file for NetBeans RCP projects, which Hans Dockter from the Gradle team is helping me with.