When you access PlayN's site you see that PlayN's logo uses Google colors: http://code.google.com/p/playn/
Also, Lilli Thompson talked about PlayN at New Game Conference in 2011 as a Google game developer advocate. http://www.youtube.com/watch?feature=player_detailpage&v=iK9Xl58IxKw&t=4 (I haven't watched the video.)
But she's not at Google anymore (http://plus.google.com/111647958621817995641/posts/EVptyYGHSfd and http://twitter.com/lillithompson/status/183299616647811072)
However, When you visit https://developers.google.com/games > Web games or > Mobile Games, there's no reference to PlayN. You find Android development, which links to http://developer.android.com/sdk/index.html. There's a Google Play Game Services (GPGS) too, that offers social features (achievements, multiplayer, leaderboard) for game development for Android, iOS and Web (http://developers.google.com/games/services). There are "Getting started" tutorials for GPGS for each platform (Android, iOS, Web). No PlayN, which compiles to these three platforms plus Java desktop.
So, is PlayN really supported by Google? Or was it once, and now the community is by itself?