I am somewhat skeptical too. 10 or 15 years ago this would have been great news and would have neatly side-stepped most of the negative attitudes to Perl arising from the schism. However, now that so much water has flown under the bridge and the naming situation was finally resolved last year the potential marketing gain from this is relatively minor.

So for me it all rests on the backwards compatibility. Haven't we all seen how just a few minor incompatible tweaks in recent releases have caused significant numbers of problems? I'm think here mostly of the removal of '.' from @INC and the inability to write for my $foo qw/bar baz/ {...} which broke lots of existing and important modules, many of which remain unpatched.

What I would like to see is a minimally-transparent way to have perl7 behave exactly like perl5 with no caveats. The only way I can see to do this is with an environment variable. It could be set once per server (and overridden per user/app/whatever) and then the job is done. If that can happen (and be thoroughly tested) then I'll be prepared to throw my inconsiderable weight behind it.

The announcement by contrast only mentions a pragma (compat::perl5) which might be usable via $PERL5OPT (or $PERL7OPT more likely). So if we can set PERL7OPT=-mcompat::perl5 then that should be manageable. It's still going to require extensive testing, of course.

In the meantime, I will continue to forge ahead with perl5.