While, GWT is a very impressive feat of technical accomplishment. It really misses the mark, the problem with it as well as most of the old desktop development (languages, toolkits, frameworks) is that it favored the developer over the designer. This is one of the reasons for the popularity of the web, it allowed the designer (and the want-to-be designer) the ability to design and build interfaces without having to know a turring complete languages.<p>When I first started looking to do more dynamic web applications, I was convinced that toolkits like GWT and Echo2 where they way to go but I was reasoning from a Java developers perspective. It makes the job of a Java developer easier, while adding complexity to the task of the designer. This is all well and good when you have a 1-5 man team of experienced Java developers.<p>I now prefer to use Java (Ruby, C, whatever) to write business logic services on the server and use HTML, css and JavaScript on the client. by writing a UI controller in JavaScript that gets embedded into the HTML file via a script tag it gives very clean separation of HTML, CSS and code this allows a large team to work very productively. Designers work in HTML, CSS. UX developers work in pure JavaScript and business domain developers work in their language of choice.<p>This coupled with a CMS has allowed us to abandon the kludge of a server side document scripting language (asp, jsp, php) entirely and significantly reduced the complexity of delivering a web application.