I have just released a beta version of the Groovy Template module for Play Framework 2.0 called gt-engine-play2.
The current project-status is Beta as of 24. january 2012.
It is based on the gt-engine described in this blog post.
It should be feature complete (for Java) but please have a look at the readme file over at github – and the issues-list. When you find new issues, please report them via github.
Please try it out and start porting you Java Play 1.x app to Play 2.0 
-morten