The original plan, as I recall, was to move everyone to the Parrot VM, such that there would be a Perl 5 compiler, a Perl 6 compiler, a your-language-here compiler, and everyone would be able to share code in an environment that was similar to the JVM but friendlier to dynamic languages.

So Perl 5 was never going to go away like Perl 4 had, it was just going to become one element of a broader ecosystem.