* Multi-module support to easily build multi-module projects with cross-module dependencies.
* Incremental build support for faster builds.
* Less code to write for builds through DSL.
* Better dependency management and caching.
* Convention-over-configuration so you don't have to write code if you stick to the convention, but this still possibilities to extend with extra build logic for flexibility.
* Support for enterprise wide deployment of Gradle and build conventions and tasks.
Also bigger projects like Spring, Hibernate and Grails are already migrated to Gradle for their builds.
subject: Gradle Effective Implementation Guide: What can Gradle do that Ant can't do?