Find it here:
Battles over Charles Darwin’s legacy and the implications of his theory are central to current debates on evolution. Darwin’s extensive correspondence shows, as nothing else can, how he arrived at his published views. Here, two Darwin experts [Paul White & Alison Pearn [she's not in the podcast, actually] from the Darwin Correspondence Project] talk about their current work on Darwin and evolution.
Direct mp3 here. I have yet to listen to it, but please do comment on it if you have…
UPDATE: There is also a video of the slideshow for the lecture, worth watching for the clips of the play Re:Design toward the end. Download by clicking here.