From Diablo Wiki
A podcast is an audio file composed primarily of spoken words, often reminiscent of a radio program. Podcasts can cover any and all topics, and have grown popular as a means to quickly disseminate content, editorial, or interviews with much less work for the creators than typing up the material into an article.
Gaming podcasts have become quite common and popular, and there are several active podcasts centered on Diablo III. Blizzard Entertainment semi-regularly posts their own podcast, BlizzCast, which generally features a developer interview along with discussion of one or more of their ongoing game development projects.
Listing updated in May 2012, with several new podcasts added.
The Westmarch Workshop is recorded live, usually on Wednesday nights and is hosted by Neinball and Leviathan, both of whom got their start on The Diablo Podcast.
Shattered Soulstone -- Nevik, Breja and Jen bring you news, discussion, history and stories from their times in the world of Sanctuary past and present.
The Worldstone Keep podcast covers the Diablo community, with a focus on lore and artwork. Episodes are posted at TheWorldstoneKeep.wordpress.com.
Diablo off the Record -- Join the hosts, Evarwyn, David Adams and Liz “Mistress LeBeau” Jurgens as they discuss Diablo 3 official and community news, classes and skill trees, lore, week in-game, hardcore characters and even the franchise as a whole from past to present!
The Elitists. A Blizzard-focused podcast starring Tristan Johnson and Andrew McGowan. Episodes specifically focused on Diablo can be found here.