Dart and GWT both share the goal of enabling structured web programming. In fact, many of the same engineers who brought you GWT are working on Dart. We view Dart as an ambitious evolution of GWT’s mission to make web apps better for end users, and we’re optimistic about its potential. As Dart evolves and becomes ready for prime time, we anticipate working closely with the GWT developer community to explore Dart.
Meanwhile, rest assured that GWT will continue to be a productive and reliable way to build the most ambitious web apps — and even games like Angry Birds. Key projects within Google rely on GWT every day, and we plan to continue improving (and open-sourcing) GWT based on their real-world needs.