I think resource filtering in gradle should be easier and more convenient. I actually think it should be more maven like, but obviously without the XML. I wrote an article about how difficult it was to do something so simple (http://jlorenzen.blogspot.com/2013/06/resource-filtering-with-gradle.html).
Specifically if gradle could just let the user define the includes and excludes list say under the processResources and processTestResources task (or whatever it is). I think this approach would be much more simple if possible. Then as long as the properties were defined on the command line, project gradle.properties, or user home gradle.properties, and the resource files contained the necessary default token @@, then gradle should automatically do the resource filtering.