Not all is lost for Perl5. A hash containing subroutine refs can be equally readable, though fall-through can be difficult to achieve. It also has the advantage of having O(1) efficiency, just like switches in C (an interesting discussion of which is here).

In C switches, you trade off some flexibility for efficiency. Perl6 switches will allow any expression to be used as a case, so they're basically as efficient as a bunch of if/elsif statements (though I'm hoping simple cases will be optimized into something like a C switch).