Yahoo has launched a podcasting site, a place that's not only a directory of podcasts but also a great resource of rich information on podcasting generally, and a one-stop-shop for your podcasts and music purchasing.
Yahoo Podcasts includes detailed information that explains what podcasts are and an excellent how-to guide on creating your own podcast, how to create the RSS feed, get listed in podcast directories (there's a list of other major directories) and much more.
In addition, you can get the Yahoo Music Engine, a desktop application/plug-in for Windows with similarities in concept and functionality to Apple's iTunes - you can listen to music, CDs, LAUNCHcast Radio and podcasts, as well as burn CDs and buy music downloads (at $0.79 a track compared to iTunes' $0.99 in the US).
What will likely be appealing to many people is that Yahoo's offering supports both the WMA file format as well as the MP3 file format (used by a wide range of portable digital players), and Apple's AAC file format (used only by the iPod range). More info here. Some people might not like Yahoo's all-embracing approach to Windows Media DRM (digital rights management), but you'd better get used to it - this is arguably the future of digital media and how it's made available online.
There can now be no doubt - podcasting has entered the mainstream.