I've ordered Advanced Perl Programming and Mastering Algorithms in Perl.
These two, should fill you for a while and even give you the direction for next learning. While you are there, also read "Object Oriented Perl", "Perl for Sys admin" and "Network programming with Perl", depend upon the area that you are interested in.
A repository of your skill set can also be a good starting point. You might be interested at some point, is how you have been managing what you have learned. Where do you put it to use etc.