It's Keynote. I recorded those sessions as screencasts, then sliced them into tiny pieces so I can advance them perfectly with my talking. There are 37 slides in that four-minute talk. In some cases, the slices are only two or three frames long.
I like the sliced screencasts because they're so repeatable. I practice my talks a lot, and I can get the timing down perfectly because it's always the same. Highly recommended. :)
