What is on Your Mind?

Furthermore, you'll probably be using BASH or KORN to run your perl scripts, so you might as well learn to use it.

Shell scripting will allow you to quickly perform more involved commands. And, you will more naturally learn as you chain one process into the next. For instance, you probably already know the ls command, but you can combine it with other commands to get (perhaps) better info. Thus, you could ls | grep "smith" to find filenames with "smith" in them. Next, you might decide to do a loop around those results to determine whatever.
Anyway, shell scripting is simply an extension of the shell commands.

So... I would start with shell scripting.

learn them both but learn shell scripting first. I suggest sh or ksh first and then bash. This will allow you script easily on systems that don't have bash. learning Perl after will allow you to appreciate the language.

and don't forget about basic sed/awk/grep.

for system administrators i would suggest Perl because of its portability.

I would say learn both of them and when using
" use the right tool for the right job "

Agreed, and Frank, you too.

find /my/dir -maxdepth 1 -type f -not -name *bz2 -exec bzip2 {} \; FTW baby!

None of this ls stuff, BASH is where the action is at.
And perl is where the trickiness is made do-able.

while (<>) {
if ($_ =~ /\S+ (\S+)\s+(\d+)/) {
print 'Index ' . $1 . ' has ' . $2 . ' functions.' . "\n";
}
}

Then mix them together:
find /my/dir -maxdepth 1 -type f -not -name *bz2 |my_perl.pl |grep -i "fancy" |awk '{ print ( $4 }' |less

Feel the powers for different tasks...

I mean lets be honest you cannot sys admin without BASH (or SH/KSH)

BASH has regular expressions these days, you know. No need to run 2 or 3 interpreters to do one job.