Magnatune now automatically streams "ogg" file format audio to you, when you browse the magnatune web site, if your web browser supports it (it's the default now for Firefox).
The main advantages of this are:
1) about 1/3rd less bandwidth used, and better sound
2) enables users who don't have flash enabled to stream music from Magnatune
3) it's totally automatic, you won't have to do anything
4) uses non-patented, open standards and open source technology
A few of you wrote in saying you were having trouble streaming music from Magnatune on your linux browsers. I am pretty sure this is because flash isn't installed, and your browser won't play a non-free format by default. Previously, MP3 files were always used, even (whoops) if your web browser couldn't play them.
Now, if your web browser supports OGG files, those are used if you can't play MP3 files. Better sound quality, and less bandwidth, good stuff!
Flash block extension users: in most cases Magnatune will now automatically recover from Flash being blocked in your web browser. However, I can't get this to work with Flash Block in Firefox, so HTML5 audio playback is not used if you have Flashblock enabled (a few features disappear). If you either "whitelist" Magnatune for flash playback or remove flash entirely, there is no problem.
Why not OGG always? I tested using OGG files in preference to MP3 files, and found that Safari, while it said it was playing the OGG file, actually made no sound. Same with M4A files in Safari, whereas MP3 files played fine. So... at least for now, OGG support is still a bit buggy.
However, Firefox handles OGG files perfectly, so it's the default if you're a Firefox user.