I didn't see exactly which piece of software that Adam was using for his audioblogging, but I would recommend Total Recorder Live for recording audio on a Windows PC.

You can record sound using a special audio driver that can also automatically remove any Windows sound events from the recording. Or you can just set it to record off the speaker out channel. Once you finish recording, you can save to just about any format (including MP3). The Pro version includes more editing/advanced functionality.

Postscript: Actually, I just heard the software (WireTap) described on the August 27 Source Code audioblog post.
5:31:18 PM