I haven't tried, but most of the apps/widgets on TiVo have always been somewhat problematic(I have a premiere). That being said, I love my TiVo -but since I've had the AppleTV I haven't had the need to use TiVo for podcasts, YouTube, Netflix, etc. The TiVo was generally slow to start these apps and while the picture quality is more than acceptable -AppleTV converts to 1080p(I think) and is noticeably better on my TV.
If you use Youtube on your TiVo and sign in, you can watch the podcasts just fine. But you'll need to have a YouTube account, and go through the sign in step to allow access through TiVo. All you need yo do other than that is to subscribe to TheDIS YouTube feed. Does that make sense?