Indeed, OpenJDK on the Pi is so slow it’s little more than a curiosity. Hardfloat hotspot just around the corner though. I can wait.
Cas 
It’s a bit exaggerated, you could run some nice 2D Java games on it.
What about Shark JIT?
I had the impression that shark was more or less dead since the redhat dude changed positions…is this incorrect?
All of these mickey mouse techs all lead down the same path - incompatibility, hair pulling, and above all… shite performance. There’s only one bad boy in town and it’s the Oracle embedded JVM for ARM hardfloat, and that’s just around the corner. I’m sure I could make a 2D game with Zero and OpenJDK… if I didn’t mind it running at 15fps. Which I do. A lot.
Cas
The real downside for Java to me is the lack of support for accelerated graphics on the Mac platform. Apple has a terrible JVM, and even though it mostly works, you won’t be doing anything silky smooth if you stay native to Java (no JNI). I went ahead and wrote a bunch of C++ wrappers for all of the Java objects I use just to future proof.
My friend who does graphics and design on our project uses a Mac, and while the editors and engine works, it works like shit. Until we have really great JVMs on all platforms, we’re f**ked. Sorry, but it’s true. At least with something that compiles to machine code, you’re solid.
I see Java as a development platform, but these days, with as many platforms as there are, any language you write in might as well be pseudo code. I plan on releasing in the Lingua Franca for any given platform, which is probably some variant of C.
Antiharpist
Er… the JVM on the Mac is state-of-the-art. And it’s got both LWJGL and JogAmp. And JavaFX too I believe.
Cas