I'm therefore judging the Best Fancast entries largely - but not entirely - on the basis of what's in the Hugo voter packet - a single release from each of the series, though a more informed voter would have been listening to all of them all year and would be able to judge on the basis of the sequence as a whole. I'm therefore aware that judgements on the particular episodes in question may not be fair when applied to the entire series. But I'm afraid that's the breaks.
As with the Best Fan Writer category, I'm going to list them from top to bottom of my ballot paper.
1) Galactic Suburbia - specifically Episode 32 - worked really well for me; three Australian women discussing what they enjoy within the genre with tremendous humour and enthusiasm; also generally decent production values (only StarshipSofa is better on that score), and a varied and interesting agenda. If I take up podcasts as a habit I will start here.
2) SF Squeecast - specifically Episode 7. Very nearly as enjoyable as Galactic Suburbia, but slightly more difficult to listen to, and the discussion with five people all talking from different places gets a bit confused in places, reminding me of work teleconferences (and not really in a good way). Still, good fun.
3) The Coode Street Podcast - specifically Episode 65, included with the Hugo Voter Package, and Episode 77, which I listened to shortly after it was first released. Both feature the two regular hosts with a female interviewee, in one case author Jo Walton, in the other the ten-year-old daughter of one of the regulars. While the conversation is interesting enough, having a single guest means less variety of topic, and also less entertaining banter than one gets between a regular cast of contributors. Also the sound quality in the Walton interview was not always great (she is perfectly audible but her interviewers aren't).
4) The SF Signal Podcast - specifically Podcast #26 on e-book publishing, a subject which I have seen discussed much more satisfactorily in on-line formats (where one can easily link to supporting evidence and statistics rather than appear to be randomly quoting them). I felt it was using new technology to replicate the experience of being at a convention panel, which seems a bit like reinventing the wheel; the others listed above exploit the possibilities of the podcast format much more imaginatively. I note that the episode description says that the Podcast had "given our regular panelists the night off" and wonder if they might have been better advised to submit an episode which included the regular panelists for the Hugo Voter Package.
5) StarShipSofa - specifically Episode 201, which features a monologue by a biologist, a reading of half of a Geoffrey A. Landis story, and an interview with an author I hadn't read; much the longest of the files in the Voter Packet at 86 minutes. StarShipSofa won the Hugo for Best Fanzine two years ago, and it is basically an audio version of a fanzine, rather than a podcast, and really seems made for a different decade than the other nominees. The audio quality is better than any of the other nominees by far, perhaps because (apart from the interview) it consists of recorded sequences of single speakers put together. I was frankly disappointed - I had listened to the StarShipSofa interview with Fred Pohl and Jack Vance in 2010 and hugely enjoyed that, but this really didn't do much for me.
But if the Hugo voters want audio fanzines and/or audio versions of convention panels, then I guess my preferences will be outvoted.
See also: Best Novel | Best Novella | Best Novelette | Best Short Story | Best Dramatic Presentation (Short Form) | Best Professional Artist | Best Fan Writer | Best Fan Artist