Let me start by saying that I am a huge fan of WNYC in general. I think Radio Lab is one of the best podcasts anywhere on the web. That said; I think Please Explain is not up to snuff.
All in all the subjects are interesting but the interviewer was unprepared and the final product was tedious to listen to.
The first episode I heard was informative and interesting- but had nothing at all to do with it's category of Natural Science (march 21, 2008, Media Ethics).
To be fair I tried a second (March 14, Proprioception) which was properly categorized but over and over again Mr. Lopate asked questions in his interview about the sense of balance which, while related to proprioception, or kinesthesia, is actually a separate system in the body.
Once would have been enough for the subjects to explain that the systems were related but fundamentally different.... over and over he asked in different form, as if he didn't realize he'd already gotten the response. The subject was proprioception- he insisted on making the entire interview about balance. Bad interview.
Hope this helps.