Funny how people claim Py3k was DOA. I don't know anyone who uses Perl 6 for anything serious. I'd bet that there are 100 times as many Python 3 programmers as there are Perl 6 programmers.
I think Perl 6 still has a chance, though. No reason to dismiss it just because it's developing slowly.
The compatibility mode doesn't do Perl 6 much good, if you ask me. There are already too many ways to write Perl, if you ask a Python programmer. It's like writing C in C++.
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.
Perl 6, is a major incompatible release. Its like compressing years of deprecation cycles in one major release. Larry wall realized long back that a few problems with Perl 5 can be fixed with incremental releases.
I think there is CPAN compatibility mode, and Perl 5 programs are expected to run on Perl 6 compilers. Also Perl 6 is a total redesign but preserving the 'perl spirit' and its original design principles.
OTOH, Python is taking the path of incrementally correcting its problems at the expense of breaking compatibility as and when needed. The problem is every time you break backwards compatibility, you forcing an upgrade timeline on users and during that you are allowing rival languages and communities to flourish.
If people are using Python because it just 'works', then in its absence they will use something else too if it 'works'.
Me personally if I knew that a particular tool is going to continuously break my code base every now and then. I would avoid it all costs.
Perl 5 (or, more accurately, CPAN) compatibility mode is only really interesting in two cases: when converting a project piecemeal from Perl 5 to Perl 6, and in the time between when Perl 6 gets generally usable and when it gets sufficient library support with native Perl 6 code.
All of this depends on Perl 6 being generally usable and having a working Perl 5 compatibility mode.
I think Perl 6 still has a chance, though. No reason to dismiss it just because it's developing slowly.
The compatibility mode doesn't do Perl 6 much good, if you ask me. There are already too many ways to write Perl, if you ask a Python programmer. It's like writing C in C++.