The Mac Power Users at 5by5, Katie Floyd and David Sparks are both GTD fans. Although of course it is catered toward mac users, this is a great listen for anyone — much of the discussion applies to GTD philosophy and practice in-general, and many of the apps and programs discussed will interface with PC as well (just don’t tell the Mac Power Users we told you!)
David Allen has a knack for keeping it fresh with each interview, and this is no exception! Enjoy!