The following podcasts have been enjoyable for me:

• Steve Gibson and Leo Laporte’s "Security Now" #8 (DDOS) and #9 (Rootkits).  Two good links from the podcasts: RootkitRevealer and iPhantom.
• Killer Innovations Podcast has some great stuff to make you think about how to innovate better.
• 43Folders.com has started podcasting via ODEO.
• The Mike Tech Show has a good pointer to a PDF about a "recently capture spyware vendor discussion"

Some new stuff that might be worth checking out:

• If you use PhotoShop, you might want to check out PhotoShop Radio.
• PodSqod is published great audio tools (hardware and software) reviews.
• eWeek has started podcasting.
• CastSource is offering video and podcast search options (seems to be teaming up with Yahoo).