One of the best podcasts on writing has to be I Should Be Writing.
Mur Lafferty has been doing this podcast for a number of years now. She started as a non-published (novel wise) author but not too long ago she had one of her books published. Mur also has podcasted a few novels as well. The podcast includes lots of writing advice and interviews with other authors. She is also coming out with a pdf version of the podcast.
Everyone I've talked to about the podcast has enjoyed it. Mur is fun, and great to listen to. I look forward to every time I see she has posted another podcast.
Adventures in SciFi Publishing.
This is for those interested in reading and/or writing scifi. The two hosts are very lively, and interesting to listen to. Also, this one has several interviews with authors and a few other people in the industry. Entertaining and informative.
Has a number of authors but three or four of them are the main ones that host the podcast. All of them are interesting and have good tips on writing. A few of them studied at BYU, which I find interesting since I live in Utah. But don't worry, the writing is all open to many topics, including violence. Plus, this is a very short podcast, so it won't take long to listen to each one.
For erotica writer's there is a podcast called "Packing Heat".
The creator is not quite as outgoing or crazy as some of the other ones I've mentioned but she has some good advice sometimes. I like to listen to her because she also writes gay male stories, though her focus is on the straight female audience. Aside from talking about erotica, there are topics of computer tools and writing advice.
There are many other writing podcasts, some of which are by writers and others are interviews with writers. Check them out if you get the chance.