Python 3 has been available and usable for quite some time. Not so Perl 6.
However, CPAN compatibility would be hugely important to a usable Perl 6, by simple fact that no other language has the breadth and quality and availability of libraries to rival the CPAN.
However, CPAN compatibility would be hugely important to a usable Perl 6, by simple fact that no other language has the breadth and quality and availability of libraries to rival the CPAN.