How much fundamental of the Camel was really obsoleted by 5.6.* or 5.8.*?
Well, first of all, the Camel isn't a book about fundamentals,
it's a reference guide. I'd say, the camel is as obsoleted
in three years, as a book about important CPAN modules does
in three years. How many fundamental modules arrived on CPAN
the last three years?
Declaring variables is still the same. Looping and conditionals are the same. Declaring subroutines is the same, with at best a few attributes being added, if anything. Builtins are pretty much the same, with a few details being different. Complex datastructures, packages/modules, and OO programming are the same
None of that has changed much since 5.000, and many
fundamental things haven't changed since perl4, or even
earlier Perls. If you look at fundamentals, even the pink
Camel still isn't obsolete. Some important things that have
changed from 5.6.* to 5.8.*, and are either missing from
the Camel, or insufficiently documented: Unicode support,
threading support, Perl I/O layers, signals, and a whole
bunch of new modules.
Look, it's fine if you don't want to call the Camel outdated. But then, be consistent, and don't call other
(hypothetic) books outdated either.