[joezydeco]

Dalvik has a pretty robust JNI implementation, and you can certainly put native code in an Android application. The NDK is getting more and more useful every release, and there's always building with the full distribution to have access to everything else. I've done it, and it's not that painful. I only worry about what might happen if Android starts showing up on other architectures. You'll have to pack in libraries for every single architecture.

I applaud Rubin's team for choosing Java as the high level library and UI implementation. While ObjC might be speedier on iPhone, it's a huge learning curve for someone that wants to write a UI-heavy app.