Hi,
I did a show on the net in 1999 through 2001, and in those days, you kinda had to have a server and beam it up from an ISP, since Internet connections were not strong enough for any streaming for residential accounts, and many of them were dial-ups ... our own ISP had over 75% dial-ups.
We used Unix on the server and Real Audio's software for running it and it had a cap on 25 feeds at any one time. And I added shows ever other week or so, and for the most part I did my thing, and would not allow myself to do what everyone else did, which was the same old **** and more ship, and more deepsheepdip.
By the time the show was taken down by the new owner of the ISP, who thought I was stealing his precious bandwidth of piss, I had 117 to 125 hours (lost the complete list ... I wish I had not lost it!), of music, and what I did was to show case bands and their families instead of playing hits, and only one show had 5 or 6 things, in it that were slightly related but not exactly a hit show. I followed Guy Guden's motto, of none of the hits none of the time, mainly because anyone could get what they wanted elsewhere ...
Some examples:
Man/Neutrons/Help Yourself (over 2 hours)
Family/Streetwalkers/Roger Chapman (almost 2 hours)
Gong/Gilly/Steve Hillage/Pierre Moerlin's Gong (2 hours)
Stackridge/Korgis/Greenslade (almoat 2 hours)
Can/Czukay/Schmidt/Phantom Band (3 hours)
Banco (1 hour)
PFM (1 hour)
Ange (2 hours)
Grobbschnit/Eloy/Jane (2 hours)
Guru Guru/Kraan (2 hours)
Focus (hour and a half)
Caravan (2 hours)
Hipgnosis/Harvest Show (2 hours)
Roy Harper (2 hours)
ECM show with Garbarek/Gismonti/Haden/Walcott/Abercrombie (3 hours)
And several more shows most of which fail my memory at this time. It was called "The Space", and for my tastes it was an "anti-radio" show.
Nowadays, things are a bit different and with mp3 being able to be done in low resolution, you can do an hour really easy and it is not a strain on a server anywhere, and most places, like 365 and the ones you mention are OK, with one exception (and this is personal for me!), they don't know the music, don't care, and only want to "rent" you the space, thus, if you are a beginner and trying out to get space for your band, or simply showcase your thing, you have to pay for it. OR, find a way to trade out with them, for some commercial venture of your own, which may be harder to do, if you want to deal with some megalomaniacs that are not interested in anything you have except ... the money ... use that CC! ... shut up ... do your thing, but pay for it.
A couple of the others you mention I have not checked, and as I say, I have not taken this any further although I have had one discussion with my web hosting folks about this, and I might just do another show through them, since it will be an exclusive thing and not exactly a show that will get 10K hits on one night, though you never know ... one day ... KABOOM ... and you have to make changes, but on that day, that company you work with wants you there and will consider marketing investments so you can bring some money home, also.
This is as much as I know, and "podcast" for me is just another show ... for the same thing, and my only interest is not doing what someone is already doing. As much as I like LZ, I am NOT going to play any!