Don't know about GWT but Grails with its underlying use of Groovy, Spring and Hibernate is coming out strong with its convention over configuration approach borrowed from ROR.
With awesome RIA frameworks like Extjs I also see grails getting used in the serverside as data service layer with its excellent support for JSON.
With awesome RIA frameworks like Extjs I also see grails getting used in the serverside as data service layer with its excellent support for JSON.