The Vaadin team released version 0.3 of the Vaadin plugin for Gradle. The plugin itself and a short introduction is available on github (https://github.com/johndevs/gradle-vaadin-plugin/tree/0.3). To learn more about setting up a Vaadin project with Gradle, you should have a look at the screencast available at http://www.youtube.com/watch?v=opjN3xlQ9Xk
cheers, René