I'm co-organizing the Python meetup group in San Diego and we have held two Intro to Python workshops as well as two Intro to Django workshops in the last six months.
I agree with Josh and Bryce, know your audience. We had five or six volunteers and 25 attendees. Our audience was mostly beginners and maybe 5 people who had experience in another language. We mentioned Object-Oriented programming at the end but didn't go into detail, because it's a whole topic by itself. Here are our slides for reference:
The other thing we learned is that it helps to have two projectors. So you can have one projector with a Python shell running and the other projector with the presentation. Then your audience can follow along copying what you type.