perl6-meta is in limbo right now; we need impetus, which should come when Larry releases his design
The detailed design and implementation will take a lot of careful management to happen smoothly. I believe that Nat Torkington and Dan Sugalski are up to the job, and I hope to be able to help out as well.
Will an alpha be ready for TPC 5.0? Who knows. I hope we'll have something to show off, but I also hope the world understands what "alpha" means, and doesn't expect a fully fledged Perl, because it won't be. I'm guessing we'll present a design, but no working code beyond individual modules of no use in the real world.