Just to give everyone a heads up, I have made some changes to one of my sessions. Based on the feedback I received earlier, my session on Object-Oriented Drupal has been updated. It seems no one wanted to hear about the basics, as they already knew them. :-) I will instead be focusing on design patterns, OO design philosophy, and how it applies (or should apply) to Drupal. It's too late to get changes into the printed program, but I have updated the session page on the DC DC web site to reflect the new focus.
So if you were hoping for a session on basic PHP OOP syntax and concepts, um, sorry. If you're looking for an intermediate to advanced session on how to use OOP well, then this session is for you.
I'll see you in DC!