Parrot is the virtual machine originally designed for Perl 6.
What technical capabilities does the Parrot VM offer that competing virtual machines such as the Java Virtu
I don't know JVM and CLR enough, but my tips:
Update: This is probably irrelevant as JVM is one of Rakudo Perl 6 backends nowadays. See Rakudo Perl 6 on the JVM (Perl 6 Advent calendar 2013, Day 3).