NOTE/UPDATE: This project is deprecated/discontinued. New users should consider looking at the Codehaus gwt-maven-plugin (mojo.codehaus.org/gwt-maven-plugin/). The codehaus plugin merged in the code from this plugin (maven-googlewebtoolkit2-plugin) at one point and supports most of the same goals (and should be up to date). Fore more information see the mailing lists and various threads on the status and difference between the projects: http://groups.google.com/group/gwt-maven/browse_thread/thread/6ff5102700e6de3c.
Maven is a build and "project management" tool developed by the Apache Software Foundation. GWT-Maven is a "plug-in" that extends Maven to add GWT related support and goals.
There are multiple versions of GWT-Maven, a Maven 2.x version and a Maven 1.1 version.
Both versions have the same set of basic goals (which are optional):
Maven2 docs: docs/maven-googlewebtoolkit2-plugin
Maven1 docs: docs/maven-googlewebtoolkit-plugin
Maven2 source: maven-googlewebtoolkit2-plugin
Maven1 source: maven-googlewebtoolkit-plugin
Support JAR (used by both versions to perform common tasks): maven-googlewebtoolkit-support
The Wiki also has additional information, including FAQs and upcoming plans.
Used for GWT-Maven and other related libraries.
Repo has M1 and M2 style layout within it. In the future the repo may be moved and re-organized into separate M1/M2 repos.