I look forward to your talk in Vienna.
I presume you are going to cover Damian's Parse::RecDescent - I would hope that you do so in some detail. Although it doesn't cover every situation, it is a tool that can enable parsing applications to be developed rapidly. When it comes to P::RD's autotrees, I wrote a module Parse::RecDescent::Topiary that assists in getting the trees in the shape you want them (properly constructed objects), rather than how Parse::RecDescent generates them.
It may be worth covering the history, and including YACC and LEX in the scope. Knowledge of bottom up parsers and how they differ from top down, is useful.
(Qualified NLP Practitioner and Hypnotherapist)