Rakudo is the leading Perl 6 compiler. Imo, at least in the short term (2013), where Rakudo goes, Perl 6 goes.
1. Getting to Rakudo on JVM
* First, I recommend folk consider reading the outstanding blog post rahulsundaram linked.
* http://pmichaud.com/2012/pres/yapcna-perflt/slides/slide3... is a slide from a fun 5 minute lightning talk (video at http://pmthium.com/2012/09/a-rakudo-performance/). This slide shows the ratios of the four languages used to implement the Rakudo compiler: Perl 6, NQP (a mini Perl 6), C, and PIR (Parrot Intermediate Representation) code. The sliver of PIR is a few weeks from being driven to zero.
* Once the NQP port to JVM is done the Rakudo Perl 6 compiler can be ported (jnthn clearly expects the whole Rakudo to be ported by yapcna, Austin TX, June 3-5.).
2. What Rakudo on the JVM means for Rakudo
* As http://perl6.org/compilers/features shows, Rakudo is deficient on Unicode and related items, native types, and threads. (It's arguably ahead of Perl 5 on all three of these, but it's deficient relative to the Perl 6 spec.) Rakudo devs claim these had been held up by problems related to Parrot and that the JVM will provide a suitable backend to get these functionality pieces nailed down. Note that JVM functionality that enabled completion of the Perl 6 spec and Rakudo implementation, not speed, was the primary reason for porting to the JVM.
* Larry Wall recently said that speed is the #1 blocker of mass adoption of Perl 6. Although Rakudo has recently closed the speed gap in most regards compared to Niecza (another Perl 6 compiler that targets .NET) it's still dog slow in many ways. However, there are reasons to believe Rakudo on the JVM may be faster, perhaps an order or two magnitude faster, than Parrot. (chromatic seems to dispute this.) Imo, if Rakudo substantially speeds up it will be a game changer.
3. What a fast, complete Rakudo will mean for Perl 6
Larry recently said he hopes to publish a Perl 6 equivalent of "Programming Perl" (the bible for Perl 5) around the end of this year. In mid 2009 I predicted Perl 6 would reach a generally robust state around the end of 2014. I think I was about right and folk will begin adopting Perl 6 in earnest during late 2014 or early 2015.