It seems a number of people are giving two talks at PyCon 2009 (André Roberge, Jesse Noller, Tarek Ziadé, and Mike Fletcher at least), and I can add my name to that list as well: both of my proposals were accepted.
The first is a straightforward talk about code coverage testing, and coverage.py in particular. I'm hoping to have some major new features in place in time for the talk. Maybe the conference as a deadline will help get it done.
The second talk is more ambitious: how to write a C extension, in 45 minutes. Here, I've got a few options how to proceed. One possibility is to go slowly through however much of the topic as will fit in 45 minutes, making sure it is understandable and people come away with a solid footing in the beginnings of the topic. The other way to go is to blaze through as much as I can, firehosing information on the theory that people will be able to go back and read about it later, and it will be familiar to them for having heard it once from me.
Personally I prefer the second style of talk. I learn the general lay of the land, get a quick 10,000-foot overview of the landscape, hear about places to go back to learn more in depth, and so on. But others could feel battered by the rapid-fire barrage of facts with little to grab onto.
Either way, there's no way to cover even a fraction of the complex topic of writing C extensions. My main goal is to de-mystify extensions so that people coming into the talk feeling like C extensions are deep magic leave the talk feeling like extensions are within the realm of possibility.
I don't know if previous PyCons had a similar number of double speakers. If not, what does it say about this PyCon?