As you know Google will be moving the android adt plugin build system for android apps from ant to gradle which is groovy based. But, we do not know when that might be and work on the independent gradle based plugin for android app development has stopped.
The Apache EasyAnt project has just released their first incubation release, 0.9. It uses Ivy as the build model mechanism with plugins defining build tasks and build lifecycles similar to Gradle except you are still using ant.
I am going to look into how to do a plugin to create the android app build lifecycle as a stop gap for when the adt build changes from ant to gradle as I do not want fully switch to gradle just yet. At the moment the eclipse plugin easyant4e has not released any code out in public yet, however that may change soon.
The move to do this presents some interesting challenges such as can we do the ant macros used in the android app build as easyant modules/plugins. It should be interesting.