On the latter, why is that? Is it that Java's VM is already very mature and the community doesn't feel that urgency on "improving" it?
Another question. What does Java VM have to do with Android?
I'm not a mobile developer so you shouldn't ask me but basically because of web browsers there's a JS VM in every PC and smartphone nowadays which isn't necessarily the case with Java. And Android runs its applications on a Java VM called Dalvik: http://en.wikipedia.org/wiki/Dalvik_(software)
Dalvik is not a Java VM though it is a VM.
As of Lollipop Android left the whole VM thing behind and moved to ART so there is no stagnation on that front
You linked to the page that states it all but its like you didn't bother to read it yourself.