Java mobile isn't truly multi-platform to get most applications to work you need to compile different versions of the app for different devices, this has been a bug bear of Java gaming for eons. It truly sucks.

One of the problems (Device build fragmentation) will remain regardless of the language/VM implementation. This is because different handsets all have different capabilities wrt. draw speed, 3D capabilities, real VRAM, available static/dynamic RAM, CPU speed, FPU/not, storage space, persistent record space, to name but a few. The handset manufacturers aren't all going to switch their entire phones to contain a homogeneous hardware specification, just to make app porting easier on whatever VM implementation exists.

Well, the fragmentation in the market may be due at least in part to the lack of a complete Open Source toolkit ..... people re tempted to write their own, incompatible ones, and if nobody opens up their Source Code then everybody's one ends up being incompatible with everyone else's.

The existence of a GPL toolkit means that anyone can use it, without paying for it, just as long as they don't try to bogart any changes they may make to it. What's not to like?

Android only happens to run on Linux. It's essentially a Java platform using Google's Java engine and APIs instead of Sun's. Unless performance is at least x2 better, it's a pointless re-invention, like much of open sauce.

It's not Sun's fault the various Phone manufactureres don't implement Java (or MIDP etc.) properly. Having said that, I'd trust Sun over the increasingly autocratic Google and Apple any day.

Java may still have a way to go, but its still the only real cross-platform game out there.

I have Java bus timetables from my local bus company on my phone. They work on just about anything.

And I know that Java's not going to crash my phone, unlike some native apps.

Even Nokia´s official radio player app reboots my brand new Nokia phone on a regular basis.